]> git.karo-electronics.de Git - karo-tx-linux.git/blob - drivers/nvdimm/region_devs.c
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
[karo-tx-linux.git] / drivers / nvdimm / region_devs.c
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/scatterlist.h>
14 #include <linux/highmem.h>
15 #include <linux/sched.h>
16 #include <linux/slab.h>
17 #include <linux/sort.h>
18 #include <linux/io.h>
19 #include <linux/nd.h>
20 #include "nd-core.h"
21 #include "nd.h"
22
23 static DEFINE_IDA(region_ida);
24
25 static void nd_region_release(struct device *dev)
26 {
27         struct nd_region *nd_region = to_nd_region(dev);
28         u16 i;
29
30         for (i = 0; i < nd_region->ndr_mappings; i++) {
31                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
32                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
33
34                 put_device(&nvdimm->dev);
35         }
36         free_percpu(nd_region->lane);
37         ida_simple_remove(&region_ida, nd_region->id);
38         if (is_nd_blk(dev))
39                 kfree(to_nd_blk_region(dev));
40         else
41                 kfree(nd_region);
42 }
43
44 static struct device_type nd_blk_device_type = {
45         .name = "nd_blk",
46         .release = nd_region_release,
47 };
48
49 static struct device_type nd_pmem_device_type = {
50         .name = "nd_pmem",
51         .release = nd_region_release,
52 };
53
54 static struct device_type nd_volatile_device_type = {
55         .name = "nd_volatile",
56         .release = nd_region_release,
57 };
58
59 bool is_nd_pmem(struct device *dev)
60 {
61         return dev ? dev->type == &nd_pmem_device_type : false;
62 }
63
64 bool is_nd_blk(struct device *dev)
65 {
66         return dev ? dev->type == &nd_blk_device_type : false;
67 }
68
69 struct nd_region *to_nd_region(struct device *dev)
70 {
71         struct nd_region *nd_region = container_of(dev, struct nd_region, dev);
72
73         WARN_ON(dev->type->release != nd_region_release);
74         return nd_region;
75 }
76 EXPORT_SYMBOL_GPL(to_nd_region);
77
78 struct nd_blk_region *to_nd_blk_region(struct device *dev)
79 {
80         struct nd_region *nd_region = to_nd_region(dev);
81
82         WARN_ON(!is_nd_blk(dev));
83         return container_of(nd_region, struct nd_blk_region, nd_region);
84 }
85 EXPORT_SYMBOL_GPL(to_nd_blk_region);
86
87 void *nd_region_provider_data(struct nd_region *nd_region)
88 {
89         return nd_region->provider_data;
90 }
91 EXPORT_SYMBOL_GPL(nd_region_provider_data);
92
93 void *nd_blk_region_provider_data(struct nd_blk_region *ndbr)
94 {
95         return ndbr->blk_provider_data;
96 }
97 EXPORT_SYMBOL_GPL(nd_blk_region_provider_data);
98
99 void nd_blk_region_set_provider_data(struct nd_blk_region *ndbr, void *data)
100 {
101         ndbr->blk_provider_data = data;
102 }
103 EXPORT_SYMBOL_GPL(nd_blk_region_set_provider_data);
104
105 /**
106  * nd_region_to_nstype() - region to an integer namespace type
107  * @nd_region: region-device to interrogate
108  *
109  * This is the 'nstype' attribute of a region as well, an input to the
110  * MODALIAS for namespace devices, and bit number for a nvdimm_bus to match
111  * namespace devices with namespace drivers.
112  */
113 int nd_region_to_nstype(struct nd_region *nd_region)
114 {
115         if (is_nd_pmem(&nd_region->dev)) {
116                 u16 i, alias;
117
118                 for (i = 0, alias = 0; i < nd_region->ndr_mappings; i++) {
119                         struct nd_mapping *nd_mapping = &nd_region->mapping[i];
120                         struct nvdimm *nvdimm = nd_mapping->nvdimm;
121
122                         if (nvdimm->flags & NDD_ALIASING)
123                                 alias++;
124                 }
125                 if (alias)
126                         return ND_DEVICE_NAMESPACE_PMEM;
127                 else
128                         return ND_DEVICE_NAMESPACE_IO;
129         } else if (is_nd_blk(&nd_region->dev)) {
130                 return ND_DEVICE_NAMESPACE_BLK;
131         }
132
133         return 0;
134 }
135 EXPORT_SYMBOL(nd_region_to_nstype);
136
137 static ssize_t size_show(struct device *dev,
138                 struct device_attribute *attr, char *buf)
139 {
140         struct nd_region *nd_region = to_nd_region(dev);
141         unsigned long long size = 0;
142
143         if (is_nd_pmem(dev)) {
144                 size = nd_region->ndr_size;
145         } else if (nd_region->ndr_mappings == 1) {
146                 struct nd_mapping *nd_mapping = &nd_region->mapping[0];
147
148                 size = nd_mapping->size;
149         }
150
151         return sprintf(buf, "%llu\n", size);
152 }
153 static DEVICE_ATTR_RO(size);
154
155 static ssize_t mappings_show(struct device *dev,
156                 struct device_attribute *attr, char *buf)
157 {
158         struct nd_region *nd_region = to_nd_region(dev);
159
160         return sprintf(buf, "%d\n", nd_region->ndr_mappings);
161 }
162 static DEVICE_ATTR_RO(mappings);
163
164 static ssize_t nstype_show(struct device *dev,
165                 struct device_attribute *attr, char *buf)
166 {
167         struct nd_region *nd_region = to_nd_region(dev);
168
169         return sprintf(buf, "%d\n", nd_region_to_nstype(nd_region));
170 }
171 static DEVICE_ATTR_RO(nstype);
172
173 static ssize_t set_cookie_show(struct device *dev,
174                 struct device_attribute *attr, char *buf)
175 {
176         struct nd_region *nd_region = to_nd_region(dev);
177         struct nd_interleave_set *nd_set = nd_region->nd_set;
178
179         if (is_nd_pmem(dev) && nd_set)
180                 /* pass, should be precluded by region_visible */;
181         else
182                 return -ENXIO;
183
184         return sprintf(buf, "%#llx\n", nd_set->cookie);
185 }
186 static DEVICE_ATTR_RO(set_cookie);
187
188 resource_size_t nd_region_available_dpa(struct nd_region *nd_region)
189 {
190         resource_size_t blk_max_overlap = 0, available, overlap;
191         int i;
192
193         WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
194
195  retry:
196         available = 0;
197         overlap = blk_max_overlap;
198         for (i = 0; i < nd_region->ndr_mappings; i++) {
199                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
200                 struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
201
202                 /* if a dimm is disabled the available capacity is zero */
203                 if (!ndd)
204                         return 0;
205
206                 if (is_nd_pmem(&nd_region->dev)) {
207                         available += nd_pmem_available_dpa(nd_region,
208                                         nd_mapping, &overlap);
209                         if (overlap > blk_max_overlap) {
210                                 blk_max_overlap = overlap;
211                                 goto retry;
212                         }
213                 } else if (is_nd_blk(&nd_region->dev)) {
214                         available += nd_blk_available_dpa(nd_mapping);
215                 }
216         }
217
218         return available;
219 }
220
221 static ssize_t available_size_show(struct device *dev,
222                 struct device_attribute *attr, char *buf)
223 {
224         struct nd_region *nd_region = to_nd_region(dev);
225         unsigned long long available = 0;
226
227         /*
228          * Flush in-flight updates and grab a snapshot of the available
229          * size.  Of course, this value is potentially invalidated the
230          * memory nvdimm_bus_lock() is dropped, but that's userspace's
231          * problem to not race itself.
232          */
233         nvdimm_bus_lock(dev);
234         wait_nvdimm_bus_probe_idle(dev);
235         available = nd_region_available_dpa(nd_region);
236         nvdimm_bus_unlock(dev);
237
238         return sprintf(buf, "%llu\n", available);
239 }
240 static DEVICE_ATTR_RO(available_size);
241
242 static ssize_t init_namespaces_show(struct device *dev,
243                 struct device_attribute *attr, char *buf)
244 {
245         struct nd_region_namespaces *num_ns = dev_get_drvdata(dev);
246         ssize_t rc;
247
248         nvdimm_bus_lock(dev);
249         if (num_ns)
250                 rc = sprintf(buf, "%d/%d\n", num_ns->active, num_ns->count);
251         else
252                 rc = -ENXIO;
253         nvdimm_bus_unlock(dev);
254
255         return rc;
256 }
257 static DEVICE_ATTR_RO(init_namespaces);
258
259 static ssize_t namespace_seed_show(struct device *dev,
260                 struct device_attribute *attr, char *buf)
261 {
262         struct nd_region *nd_region = to_nd_region(dev);
263         ssize_t rc;
264
265         nvdimm_bus_lock(dev);
266         if (nd_region->ns_seed)
267                 rc = sprintf(buf, "%s\n", dev_name(nd_region->ns_seed));
268         else
269                 rc = sprintf(buf, "\n");
270         nvdimm_bus_unlock(dev);
271         return rc;
272 }
273 static DEVICE_ATTR_RO(namespace_seed);
274
275 static ssize_t btt_seed_show(struct device *dev,
276                 struct device_attribute *attr, char *buf)
277 {
278         struct nd_region *nd_region = to_nd_region(dev);
279         ssize_t rc;
280
281         nvdimm_bus_lock(dev);
282         if (nd_region->btt_seed)
283                 rc = sprintf(buf, "%s\n", dev_name(nd_region->btt_seed));
284         else
285                 rc = sprintf(buf, "\n");
286         nvdimm_bus_unlock(dev);
287
288         return rc;
289 }
290 static DEVICE_ATTR_RO(btt_seed);
291
292 static ssize_t pfn_seed_show(struct device *dev,
293                 struct device_attribute *attr, char *buf)
294 {
295         struct nd_region *nd_region = to_nd_region(dev);
296         ssize_t rc;
297
298         nvdimm_bus_lock(dev);
299         if (nd_region->pfn_seed)
300                 rc = sprintf(buf, "%s\n", dev_name(nd_region->pfn_seed));
301         else
302                 rc = sprintf(buf, "\n");
303         nvdimm_bus_unlock(dev);
304
305         return rc;
306 }
307 static DEVICE_ATTR_RO(pfn_seed);
308
309 static ssize_t read_only_show(struct device *dev,
310                 struct device_attribute *attr, char *buf)
311 {
312         struct nd_region *nd_region = to_nd_region(dev);
313
314         return sprintf(buf, "%d\n", nd_region->ro);
315 }
316
317 static ssize_t read_only_store(struct device *dev,
318                 struct device_attribute *attr, const char *buf, size_t len)
319 {
320         bool ro;
321         int rc = strtobool(buf, &ro);
322         struct nd_region *nd_region = to_nd_region(dev);
323
324         if (rc)
325                 return rc;
326
327         nd_region->ro = ro;
328         return len;
329 }
330 static DEVICE_ATTR_RW(read_only);
331
332 static struct attribute *nd_region_attributes[] = {
333         &dev_attr_size.attr,
334         &dev_attr_nstype.attr,
335         &dev_attr_mappings.attr,
336         &dev_attr_btt_seed.attr,
337         &dev_attr_pfn_seed.attr,
338         &dev_attr_read_only.attr,
339         &dev_attr_set_cookie.attr,
340         &dev_attr_available_size.attr,
341         &dev_attr_namespace_seed.attr,
342         &dev_attr_init_namespaces.attr,
343         NULL,
344 };
345
346 static umode_t region_visible(struct kobject *kobj, struct attribute *a, int n)
347 {
348         struct device *dev = container_of(kobj, typeof(*dev), kobj);
349         struct nd_region *nd_region = to_nd_region(dev);
350         struct nd_interleave_set *nd_set = nd_region->nd_set;
351         int type = nd_region_to_nstype(nd_region);
352
353         if (!is_nd_pmem(dev) && a == &dev_attr_pfn_seed.attr)
354                 return 0;
355
356         if (a != &dev_attr_set_cookie.attr
357                         && a != &dev_attr_available_size.attr)
358                 return a->mode;
359
360         if ((type == ND_DEVICE_NAMESPACE_PMEM
361                                 || type == ND_DEVICE_NAMESPACE_BLK)
362                         && a == &dev_attr_available_size.attr)
363                 return a->mode;
364         else if (is_nd_pmem(dev) && nd_set)
365                 return a->mode;
366
367         return 0;
368 }
369
370 struct attribute_group nd_region_attribute_group = {
371         .attrs = nd_region_attributes,
372         .is_visible = region_visible,
373 };
374 EXPORT_SYMBOL_GPL(nd_region_attribute_group);
375
376 u64 nd_region_interleave_set_cookie(struct nd_region *nd_region)
377 {
378         struct nd_interleave_set *nd_set = nd_region->nd_set;
379
380         if (nd_set)
381                 return nd_set->cookie;
382         return 0;
383 }
384
385 /*
386  * Upon successful probe/remove, take/release a reference on the
387  * associated interleave set (if present), and plant new btt + namespace
388  * seeds.  Also, on the removal of a BLK region, notify the provider to
389  * disable the region.
390  */
391 static void nd_region_notify_driver_action(struct nvdimm_bus *nvdimm_bus,
392                 struct device *dev, bool probe)
393 {
394         struct nd_region *nd_region;
395
396         if (!probe && (is_nd_pmem(dev) || is_nd_blk(dev))) {
397                 int i;
398
399                 nd_region = to_nd_region(dev);
400                 for (i = 0; i < nd_region->ndr_mappings; i++) {
401                         struct nd_mapping *nd_mapping = &nd_region->mapping[i];
402                         struct nvdimm_drvdata *ndd = nd_mapping->ndd;
403                         struct nvdimm *nvdimm = nd_mapping->nvdimm;
404
405                         kfree(nd_mapping->labels);
406                         nd_mapping->labels = NULL;
407                         put_ndd(ndd);
408                         nd_mapping->ndd = NULL;
409                         if (ndd)
410                                 atomic_dec(&nvdimm->busy);
411                 }
412
413                 if (is_nd_pmem(dev))
414                         return;
415
416                 to_nd_blk_region(dev)->disable(nvdimm_bus, dev);
417         }
418         if (dev->parent && is_nd_blk(dev->parent) && probe) {
419                 nd_region = to_nd_region(dev->parent);
420                 nvdimm_bus_lock(dev);
421                 if (nd_region->ns_seed == dev)
422                         nd_region_create_blk_seed(nd_region);
423                 nvdimm_bus_unlock(dev);
424         }
425         if (is_nd_btt(dev) && probe) {
426                 struct nd_btt *nd_btt = to_nd_btt(dev);
427
428                 nd_region = to_nd_region(dev->parent);
429                 nvdimm_bus_lock(dev);
430                 if (nd_region->btt_seed == dev)
431                         nd_region_create_btt_seed(nd_region);
432                 if (nd_region->ns_seed == &nd_btt->ndns->dev &&
433                                 is_nd_blk(dev->parent))
434                         nd_region_create_blk_seed(nd_region);
435                 nvdimm_bus_unlock(dev);
436         }
437         if (is_nd_pfn(dev) && probe) {
438                 nd_region = to_nd_region(dev->parent);
439                 nvdimm_bus_lock(dev);
440                 if (nd_region->pfn_seed == dev)
441                         nd_region_create_pfn_seed(nd_region);
442                 nvdimm_bus_unlock(dev);
443         }
444 }
445
446 void nd_region_probe_success(struct nvdimm_bus *nvdimm_bus, struct device *dev)
447 {
448         nd_region_notify_driver_action(nvdimm_bus, dev, true);
449 }
450
451 void nd_region_disable(struct nvdimm_bus *nvdimm_bus, struct device *dev)
452 {
453         nd_region_notify_driver_action(nvdimm_bus, dev, false);
454 }
455
456 static ssize_t mappingN(struct device *dev, char *buf, int n)
457 {
458         struct nd_region *nd_region = to_nd_region(dev);
459         struct nd_mapping *nd_mapping;
460         struct nvdimm *nvdimm;
461
462         if (n >= nd_region->ndr_mappings)
463                 return -ENXIO;
464         nd_mapping = &nd_region->mapping[n];
465         nvdimm = nd_mapping->nvdimm;
466
467         return sprintf(buf, "%s,%llu,%llu\n", dev_name(&nvdimm->dev),
468                         nd_mapping->start, nd_mapping->size);
469 }
470
471 #define REGION_MAPPING(idx) \
472 static ssize_t mapping##idx##_show(struct device *dev,          \
473                 struct device_attribute *attr, char *buf)       \
474 {                                                               \
475         return mappingN(dev, buf, idx);                         \
476 }                                                               \
477 static DEVICE_ATTR_RO(mapping##idx)
478
479 /*
480  * 32 should be enough for a while, even in the presence of socket
481  * interleave a 32-way interleave set is a degenerate case.
482  */
483 REGION_MAPPING(0);
484 REGION_MAPPING(1);
485 REGION_MAPPING(2);
486 REGION_MAPPING(3);
487 REGION_MAPPING(4);
488 REGION_MAPPING(5);
489 REGION_MAPPING(6);
490 REGION_MAPPING(7);
491 REGION_MAPPING(8);
492 REGION_MAPPING(9);
493 REGION_MAPPING(10);
494 REGION_MAPPING(11);
495 REGION_MAPPING(12);
496 REGION_MAPPING(13);
497 REGION_MAPPING(14);
498 REGION_MAPPING(15);
499 REGION_MAPPING(16);
500 REGION_MAPPING(17);
501 REGION_MAPPING(18);
502 REGION_MAPPING(19);
503 REGION_MAPPING(20);
504 REGION_MAPPING(21);
505 REGION_MAPPING(22);
506 REGION_MAPPING(23);
507 REGION_MAPPING(24);
508 REGION_MAPPING(25);
509 REGION_MAPPING(26);
510 REGION_MAPPING(27);
511 REGION_MAPPING(28);
512 REGION_MAPPING(29);
513 REGION_MAPPING(30);
514 REGION_MAPPING(31);
515
516 static umode_t mapping_visible(struct kobject *kobj, struct attribute *a, int n)
517 {
518         struct device *dev = container_of(kobj, struct device, kobj);
519         struct nd_region *nd_region = to_nd_region(dev);
520
521         if (n < nd_region->ndr_mappings)
522                 return a->mode;
523         return 0;
524 }
525
526 static struct attribute *mapping_attributes[] = {
527         &dev_attr_mapping0.attr,
528         &dev_attr_mapping1.attr,
529         &dev_attr_mapping2.attr,
530         &dev_attr_mapping3.attr,
531         &dev_attr_mapping4.attr,
532         &dev_attr_mapping5.attr,
533         &dev_attr_mapping6.attr,
534         &dev_attr_mapping7.attr,
535         &dev_attr_mapping8.attr,
536         &dev_attr_mapping9.attr,
537         &dev_attr_mapping10.attr,
538         &dev_attr_mapping11.attr,
539         &dev_attr_mapping12.attr,
540         &dev_attr_mapping13.attr,
541         &dev_attr_mapping14.attr,
542         &dev_attr_mapping15.attr,
543         &dev_attr_mapping16.attr,
544         &dev_attr_mapping17.attr,
545         &dev_attr_mapping18.attr,
546         &dev_attr_mapping19.attr,
547         &dev_attr_mapping20.attr,
548         &dev_attr_mapping21.attr,
549         &dev_attr_mapping22.attr,
550         &dev_attr_mapping23.attr,
551         &dev_attr_mapping24.attr,
552         &dev_attr_mapping25.attr,
553         &dev_attr_mapping26.attr,
554         &dev_attr_mapping27.attr,
555         &dev_attr_mapping28.attr,
556         &dev_attr_mapping29.attr,
557         &dev_attr_mapping30.attr,
558         &dev_attr_mapping31.attr,
559         NULL,
560 };
561
562 struct attribute_group nd_mapping_attribute_group = {
563         .is_visible = mapping_visible,
564         .attrs = mapping_attributes,
565 };
566 EXPORT_SYMBOL_GPL(nd_mapping_attribute_group);
567
568 int nd_blk_region_init(struct nd_region *nd_region)
569 {
570         struct device *dev = &nd_region->dev;
571         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
572
573         if (!is_nd_blk(dev))
574                 return 0;
575
576         if (nd_region->ndr_mappings < 1) {
577                 dev_err(dev, "invalid BLK region\n");
578                 return -ENXIO;
579         }
580
581         return to_nd_blk_region(dev)->enable(nvdimm_bus, dev);
582 }
583
584 /**
585  * nd_region_acquire_lane - allocate and lock a lane
586  * @nd_region: region id and number of lanes possible
587  *
588  * A lane correlates to a BLK-data-window and/or a log slot in the BTT.
589  * We optimize for the common case where there are 256 lanes, one
590  * per-cpu.  For larger systems we need to lock to share lanes.  For now
591  * this implementation assumes the cost of maintaining an allocator for
592  * free lanes is on the order of the lock hold time, so it implements a
593  * static lane = cpu % num_lanes mapping.
594  *
595  * In the case of a BTT instance on top of a BLK namespace a lane may be
596  * acquired recursively.  We lock on the first instance.
597  *
598  * In the case of a BTT instance on top of PMEM, we only acquire a lane
599  * for the BTT metadata updates.
600  */
601 unsigned int nd_region_acquire_lane(struct nd_region *nd_region)
602 {
603         unsigned int cpu, lane;
604
605         cpu = get_cpu();
606         if (nd_region->num_lanes < nr_cpu_ids) {
607                 struct nd_percpu_lane *ndl_lock, *ndl_count;
608
609                 lane = cpu % nd_region->num_lanes;
610                 ndl_count = per_cpu_ptr(nd_region->lane, cpu);
611                 ndl_lock = per_cpu_ptr(nd_region->lane, lane);
612                 if (ndl_count->count++ == 0)
613                         spin_lock(&ndl_lock->lock);
614         } else
615                 lane = cpu;
616
617         return lane;
618 }
619 EXPORT_SYMBOL(nd_region_acquire_lane);
620
621 void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane)
622 {
623         if (nd_region->num_lanes < nr_cpu_ids) {
624                 unsigned int cpu = get_cpu();
625                 struct nd_percpu_lane *ndl_lock, *ndl_count;
626
627                 ndl_count = per_cpu_ptr(nd_region->lane, cpu);
628                 ndl_lock = per_cpu_ptr(nd_region->lane, lane);
629                 if (--ndl_count->count == 0)
630                         spin_unlock(&ndl_lock->lock);
631                 put_cpu();
632         }
633         put_cpu();
634 }
635 EXPORT_SYMBOL(nd_region_release_lane);
636
637 static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
638                 struct nd_region_desc *ndr_desc, struct device_type *dev_type,
639                 const char *caller)
640 {
641         struct nd_region *nd_region;
642         struct device *dev;
643         void *region_buf;
644         unsigned int i;
645         int ro = 0;
646
647         for (i = 0; i < ndr_desc->num_mappings; i++) {
648                 struct nd_mapping *nd_mapping = &ndr_desc->nd_mapping[i];
649                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
650
651                 if ((nd_mapping->start | nd_mapping->size) % SZ_4K) {
652                         dev_err(&nvdimm_bus->dev, "%s: %s mapping%d is not 4K aligned\n",
653                                         caller, dev_name(&nvdimm->dev), i);
654
655                         return NULL;
656                 }
657
658                 if (nvdimm->flags & NDD_UNARMED)
659                         ro = 1;
660         }
661
662         if (dev_type == &nd_blk_device_type) {
663                 struct nd_blk_region_desc *ndbr_desc;
664                 struct nd_blk_region *ndbr;
665
666                 ndbr_desc = to_blk_region_desc(ndr_desc);
667                 ndbr = kzalloc(sizeof(*ndbr) + sizeof(struct nd_mapping)
668                                 * ndr_desc->num_mappings,
669                                 GFP_KERNEL);
670                 if (ndbr) {
671                         nd_region = &ndbr->nd_region;
672                         ndbr->enable = ndbr_desc->enable;
673                         ndbr->disable = ndbr_desc->disable;
674                         ndbr->do_io = ndbr_desc->do_io;
675                 }
676                 region_buf = ndbr;
677         } else {
678                 nd_region = kzalloc(sizeof(struct nd_region)
679                                 + sizeof(struct nd_mapping)
680                                 * ndr_desc->num_mappings,
681                                 GFP_KERNEL);
682                 region_buf = nd_region;
683         }
684
685         if (!region_buf)
686                 return NULL;
687         nd_region->id = ida_simple_get(&region_ida, 0, 0, GFP_KERNEL);
688         if (nd_region->id < 0)
689                 goto err_id;
690
691         nd_region->lane = alloc_percpu(struct nd_percpu_lane);
692         if (!nd_region->lane)
693                 goto err_percpu;
694
695         for (i = 0; i < nr_cpu_ids; i++) {
696                 struct nd_percpu_lane *ndl;
697
698                 ndl = per_cpu_ptr(nd_region->lane, i);
699                 spin_lock_init(&ndl->lock);
700                 ndl->count = 0;
701         }
702
703         memcpy(nd_region->mapping, ndr_desc->nd_mapping,
704                         sizeof(struct nd_mapping) * ndr_desc->num_mappings);
705         for (i = 0; i < ndr_desc->num_mappings; i++) {
706                 struct nd_mapping *nd_mapping = &ndr_desc->nd_mapping[i];
707                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
708
709                 get_device(&nvdimm->dev);
710         }
711         nd_region->ndr_mappings = ndr_desc->num_mappings;
712         nd_region->provider_data = ndr_desc->provider_data;
713         nd_region->nd_set = ndr_desc->nd_set;
714         nd_region->num_lanes = ndr_desc->num_lanes;
715         nd_region->flags = ndr_desc->flags;
716         nd_region->ro = ro;
717         nd_region->numa_node = ndr_desc->numa_node;
718         ida_init(&nd_region->ns_ida);
719         ida_init(&nd_region->btt_ida);
720         ida_init(&nd_region->pfn_ida);
721         dev = &nd_region->dev;
722         dev_set_name(dev, "region%d", nd_region->id);
723         dev->parent = &nvdimm_bus->dev;
724         dev->type = dev_type;
725         dev->groups = ndr_desc->attr_groups;
726         nd_region->ndr_size = resource_size(ndr_desc->res);
727         nd_region->ndr_start = ndr_desc->res->start;
728         nd_device_register(dev);
729
730         return nd_region;
731
732  err_percpu:
733         ida_simple_remove(&region_ida, nd_region->id);
734  err_id:
735         kfree(region_buf);
736         return NULL;
737 }
738
739 struct nd_region *nvdimm_pmem_region_create(struct nvdimm_bus *nvdimm_bus,
740                 struct nd_region_desc *ndr_desc)
741 {
742         ndr_desc->num_lanes = ND_MAX_LANES;
743         return nd_region_create(nvdimm_bus, ndr_desc, &nd_pmem_device_type,
744                         __func__);
745 }
746 EXPORT_SYMBOL_GPL(nvdimm_pmem_region_create);
747
748 struct nd_region *nvdimm_blk_region_create(struct nvdimm_bus *nvdimm_bus,
749                 struct nd_region_desc *ndr_desc)
750 {
751         if (ndr_desc->num_mappings > 1)
752                 return NULL;
753         ndr_desc->num_lanes = min(ndr_desc->num_lanes, ND_MAX_LANES);
754         return nd_region_create(nvdimm_bus, ndr_desc, &nd_blk_device_type,
755                         __func__);
756 }
757 EXPORT_SYMBOL_GPL(nvdimm_blk_region_create);
758
759 struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus,
760                 struct nd_region_desc *ndr_desc)
761 {
762         ndr_desc->num_lanes = ND_MAX_LANES;
763         return nd_region_create(nvdimm_bus, ndr_desc, &nd_volatile_device_type,
764                         __func__);
765 }
766 EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create);