Merge tag 'objtool_urgent_for_5.8_rc3' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6-microblaze.git] / drivers / nvdimm / dimm_devs.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
4  */
5 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
6 #include <linux/moduleparam.h>
7 #include <linux/vmalloc.h>
8 #include <linux/device.h>
9 #include <linux/ndctl.h>
10 #include <linux/slab.h>
11 #include <linux/io.h>
12 #include <linux/fs.h>
13 #include <linux/mm.h>
14 #include "nd-core.h"
15 #include "label.h"
16 #include "pmem.h"
17 #include "nd.h"
18
19 static DEFINE_IDA(dimm_ida);
20
21 static bool noblk;
22 module_param(noblk, bool, 0444);
23 MODULE_PARM_DESC(noblk, "force disable BLK / local alias support");
24
25 /*
26  * Retrieve bus and dimm handle and return if this bus supports
27  * get_config_data commands
28  */
29 int nvdimm_check_config_data(struct device *dev)
30 {
31         struct nvdimm *nvdimm = to_nvdimm(dev);
32
33         if (!nvdimm->cmd_mask ||
34             !test_bit(ND_CMD_GET_CONFIG_DATA, &nvdimm->cmd_mask)) {
35                 if (test_bit(NDD_LABELING, &nvdimm->flags))
36                         return -ENXIO;
37                 else
38                         return -ENOTTY;
39         }
40
41         return 0;
42 }
43
44 static int validate_dimm(struct nvdimm_drvdata *ndd)
45 {
46         int rc;
47
48         if (!ndd)
49                 return -EINVAL;
50
51         rc = nvdimm_check_config_data(ndd->dev);
52         if (rc)
53                 dev_dbg(ndd->dev, "%ps: %s error: %d\n",
54                                 __builtin_return_address(0), __func__, rc);
55         return rc;
56 }
57
58 /**
59  * nvdimm_init_nsarea - determine the geometry of a dimm's namespace area
60  * @nvdimm: dimm to initialize
61  */
62 int nvdimm_init_nsarea(struct nvdimm_drvdata *ndd)
63 {
64         struct nd_cmd_get_config_size *cmd = &ndd->nsarea;
65         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
66         struct nvdimm_bus_descriptor *nd_desc;
67         int rc = validate_dimm(ndd);
68         int cmd_rc = 0;
69
70         if (rc)
71                 return rc;
72
73         if (cmd->config_size)
74                 return 0; /* already valid */
75
76         memset(cmd, 0, sizeof(*cmd));
77         nd_desc = nvdimm_bus->nd_desc;
78         rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
79                         ND_CMD_GET_CONFIG_SIZE, cmd, sizeof(*cmd), &cmd_rc);
80         if (rc < 0)
81                 return rc;
82         return cmd_rc;
83 }
84
85 int nvdimm_get_config_data(struct nvdimm_drvdata *ndd, void *buf,
86                            size_t offset, size_t len)
87 {
88         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
89         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
90         int rc = validate_dimm(ndd), cmd_rc = 0;
91         struct nd_cmd_get_config_data_hdr *cmd;
92         size_t max_cmd_size, buf_offset;
93
94         if (rc)
95                 return rc;
96
97         if (offset + len > ndd->nsarea.config_size)
98                 return -ENXIO;
99
100         max_cmd_size = min_t(u32, len, ndd->nsarea.max_xfer);
101         cmd = kvzalloc(max_cmd_size + sizeof(*cmd), GFP_KERNEL);
102         if (!cmd)
103                 return -ENOMEM;
104
105         for (buf_offset = 0; len;
106              len -= cmd->in_length, buf_offset += cmd->in_length) {
107                 size_t cmd_size;
108
109                 cmd->in_offset = offset + buf_offset;
110                 cmd->in_length = min(max_cmd_size, len);
111
112                 cmd_size = sizeof(*cmd) + cmd->in_length;
113
114                 rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
115                                 ND_CMD_GET_CONFIG_DATA, cmd, cmd_size, &cmd_rc);
116                 if (rc < 0)
117                         break;
118                 if (cmd_rc < 0) {
119                         rc = cmd_rc;
120                         break;
121                 }
122
123                 /* out_buf should be valid, copy it into our output buffer */
124                 memcpy(buf + buf_offset, cmd->out_buf, cmd->in_length);
125         }
126         kvfree(cmd);
127
128         return rc;
129 }
130
131 int nvdimm_set_config_data(struct nvdimm_drvdata *ndd, size_t offset,
132                 void *buf, size_t len)
133 {
134         size_t max_cmd_size, buf_offset;
135         struct nd_cmd_set_config_hdr *cmd;
136         int rc = validate_dimm(ndd), cmd_rc = 0;
137         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
138         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
139
140         if (rc)
141                 return rc;
142
143         if (offset + len > ndd->nsarea.config_size)
144                 return -ENXIO;
145
146         max_cmd_size = min_t(u32, len, ndd->nsarea.max_xfer);
147         cmd = kvzalloc(max_cmd_size + sizeof(*cmd) + sizeof(u32), GFP_KERNEL);
148         if (!cmd)
149                 return -ENOMEM;
150
151         for (buf_offset = 0; len; len -= cmd->in_length,
152                         buf_offset += cmd->in_length) {
153                 size_t cmd_size;
154
155                 cmd->in_offset = offset + buf_offset;
156                 cmd->in_length = min(max_cmd_size, len);
157                 memcpy(cmd->in_buf, buf + buf_offset, cmd->in_length);
158
159                 /* status is output in the last 4-bytes of the command buffer */
160                 cmd_size = sizeof(*cmd) + cmd->in_length + sizeof(u32);
161
162                 rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
163                                 ND_CMD_SET_CONFIG_DATA, cmd, cmd_size, &cmd_rc);
164                 if (rc < 0)
165                         break;
166                 if (cmd_rc < 0) {
167                         rc = cmd_rc;
168                         break;
169                 }
170         }
171         kvfree(cmd);
172
173         return rc;
174 }
175
176 void nvdimm_set_labeling(struct device *dev)
177 {
178         struct nvdimm *nvdimm = to_nvdimm(dev);
179
180         set_bit(NDD_LABELING, &nvdimm->flags);
181 }
182
183 void nvdimm_set_locked(struct device *dev)
184 {
185         struct nvdimm *nvdimm = to_nvdimm(dev);
186
187         set_bit(NDD_LOCKED, &nvdimm->flags);
188 }
189
190 void nvdimm_clear_locked(struct device *dev)
191 {
192         struct nvdimm *nvdimm = to_nvdimm(dev);
193
194         clear_bit(NDD_LOCKED, &nvdimm->flags);
195 }
196
197 static void nvdimm_release(struct device *dev)
198 {
199         struct nvdimm *nvdimm = to_nvdimm(dev);
200
201         ida_simple_remove(&dimm_ida, nvdimm->id);
202         kfree(nvdimm);
203 }
204
205 struct nvdimm *to_nvdimm(struct device *dev)
206 {
207         struct nvdimm *nvdimm = container_of(dev, struct nvdimm, dev);
208
209         WARN_ON(!is_nvdimm(dev));
210         return nvdimm;
211 }
212 EXPORT_SYMBOL_GPL(to_nvdimm);
213
214 struct nvdimm *nd_blk_region_to_dimm(struct nd_blk_region *ndbr)
215 {
216         struct nd_region *nd_region = &ndbr->nd_region;
217         struct nd_mapping *nd_mapping = &nd_region->mapping[0];
218
219         return nd_mapping->nvdimm;
220 }
221 EXPORT_SYMBOL_GPL(nd_blk_region_to_dimm);
222
223 unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr)
224 {
225         /* pmem mapping properties are private to libnvdimm */
226         return ARCH_MEMREMAP_PMEM;
227 }
228 EXPORT_SYMBOL_GPL(nd_blk_memremap_flags);
229
230 struct nvdimm_drvdata *to_ndd(struct nd_mapping *nd_mapping)
231 {
232         struct nvdimm *nvdimm = nd_mapping->nvdimm;
233
234         WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
235
236         return dev_get_drvdata(&nvdimm->dev);
237 }
238 EXPORT_SYMBOL(to_ndd);
239
240 void nvdimm_drvdata_release(struct kref *kref)
241 {
242         struct nvdimm_drvdata *ndd = container_of(kref, typeof(*ndd), kref);
243         struct device *dev = ndd->dev;
244         struct resource *res, *_r;
245
246         dev_dbg(dev, "trace\n");
247         nvdimm_bus_lock(dev);
248         for_each_dpa_resource_safe(ndd, res, _r)
249                 nvdimm_free_dpa(ndd, res);
250         nvdimm_bus_unlock(dev);
251
252         kvfree(ndd->data);
253         kfree(ndd);
254         put_device(dev);
255 }
256
257 void get_ndd(struct nvdimm_drvdata *ndd)
258 {
259         kref_get(&ndd->kref);
260 }
261
262 void put_ndd(struct nvdimm_drvdata *ndd)
263 {
264         if (ndd)
265                 kref_put(&ndd->kref, nvdimm_drvdata_release);
266 }
267
268 const char *nvdimm_name(struct nvdimm *nvdimm)
269 {
270         return dev_name(&nvdimm->dev);
271 }
272 EXPORT_SYMBOL_GPL(nvdimm_name);
273
274 struct kobject *nvdimm_kobj(struct nvdimm *nvdimm)
275 {
276         return &nvdimm->dev.kobj;
277 }
278 EXPORT_SYMBOL_GPL(nvdimm_kobj);
279
280 unsigned long nvdimm_cmd_mask(struct nvdimm *nvdimm)
281 {
282         return nvdimm->cmd_mask;
283 }
284 EXPORT_SYMBOL_GPL(nvdimm_cmd_mask);
285
286 void *nvdimm_provider_data(struct nvdimm *nvdimm)
287 {
288         if (nvdimm)
289                 return nvdimm->provider_data;
290         return NULL;
291 }
292 EXPORT_SYMBOL_GPL(nvdimm_provider_data);
293
294 static ssize_t commands_show(struct device *dev,
295                 struct device_attribute *attr, char *buf)
296 {
297         struct nvdimm *nvdimm = to_nvdimm(dev);
298         int cmd, len = 0;
299
300         if (!nvdimm->cmd_mask)
301                 return sprintf(buf, "\n");
302
303         for_each_set_bit(cmd, &nvdimm->cmd_mask, BITS_PER_LONG)
304                 len += sprintf(buf + len, "%s ", nvdimm_cmd_name(cmd));
305         len += sprintf(buf + len, "\n");
306         return len;
307 }
308 static DEVICE_ATTR_RO(commands);
309
310 static ssize_t flags_show(struct device *dev,
311                 struct device_attribute *attr, char *buf)
312 {
313         struct nvdimm *nvdimm = to_nvdimm(dev);
314
315         return sprintf(buf, "%s%s%s\n",
316                         test_bit(NDD_ALIASING, &nvdimm->flags) ? "alias " : "",
317                         test_bit(NDD_LABELING, &nvdimm->flags) ? "label " : "",
318                         test_bit(NDD_LOCKED, &nvdimm->flags) ? "lock " : "");
319 }
320 static DEVICE_ATTR_RO(flags);
321
322 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
323                 char *buf)
324 {
325         struct nvdimm *nvdimm = to_nvdimm(dev);
326
327         /*
328          * The state may be in the process of changing, userspace should
329          * quiesce probing if it wants a static answer
330          */
331         nvdimm_bus_lock(dev);
332         nvdimm_bus_unlock(dev);
333         return sprintf(buf, "%s\n", atomic_read(&nvdimm->busy)
334                         ? "active" : "idle");
335 }
336 static DEVICE_ATTR_RO(state);
337
338 static ssize_t available_slots_show(struct device *dev,
339                 struct device_attribute *attr, char *buf)
340 {
341         struct nvdimm_drvdata *ndd = dev_get_drvdata(dev);
342         ssize_t rc;
343         u32 nfree;
344
345         if (!ndd)
346                 return -ENXIO;
347
348         nvdimm_bus_lock(dev);
349         nfree = nd_label_nfree(ndd);
350         if (nfree - 1 > nfree) {
351                 dev_WARN_ONCE(dev, 1, "we ate our last label?\n");
352                 nfree = 0;
353         } else
354                 nfree--;
355         rc = sprintf(buf, "%d\n", nfree);
356         nvdimm_bus_unlock(dev);
357         return rc;
358 }
359 static DEVICE_ATTR_RO(available_slots);
360
361 __weak ssize_t security_show(struct device *dev,
362                 struct device_attribute *attr, char *buf)
363 {
364         struct nvdimm *nvdimm = to_nvdimm(dev);
365
366         if (test_bit(NVDIMM_SECURITY_DISABLED, &nvdimm->sec.flags))
367                 return sprintf(buf, "disabled\n");
368         if (test_bit(NVDIMM_SECURITY_UNLOCKED, &nvdimm->sec.flags))
369                 return sprintf(buf, "unlocked\n");
370         if (test_bit(NVDIMM_SECURITY_LOCKED, &nvdimm->sec.flags))
371                 return sprintf(buf, "locked\n");
372         if (test_bit(NVDIMM_SECURITY_OVERWRITE, &nvdimm->sec.flags))
373                 return sprintf(buf, "overwrite\n");
374         return -ENOTTY;
375 }
376
377 static ssize_t frozen_show(struct device *dev,
378                 struct device_attribute *attr, char *buf)
379 {
380         struct nvdimm *nvdimm = to_nvdimm(dev);
381
382         return sprintf(buf, "%d\n", test_bit(NVDIMM_SECURITY_FROZEN,
383                                 &nvdimm->sec.flags));
384 }
385 static DEVICE_ATTR_RO(frozen);
386
387 static ssize_t security_store(struct device *dev,
388                 struct device_attribute *attr, const char *buf, size_t len)
389
390 {
391         ssize_t rc;
392
393         /*
394          * Require all userspace triggered security management to be
395          * done while probing is idle and the DIMM is not in active use
396          * in any region.
397          */
398         nd_device_lock(dev);
399         nvdimm_bus_lock(dev);
400         wait_nvdimm_bus_probe_idle(dev);
401         rc = nvdimm_security_store(dev, buf, len);
402         nvdimm_bus_unlock(dev);
403         nd_device_unlock(dev);
404
405         return rc;
406 }
407 static DEVICE_ATTR_RW(security);
408
409 static struct attribute *nvdimm_attributes[] = {
410         &dev_attr_state.attr,
411         &dev_attr_flags.attr,
412         &dev_attr_commands.attr,
413         &dev_attr_available_slots.attr,
414         &dev_attr_security.attr,
415         &dev_attr_frozen.attr,
416         NULL,
417 };
418
419 static umode_t nvdimm_visible(struct kobject *kobj, struct attribute *a, int n)
420 {
421         struct device *dev = container_of(kobj, typeof(*dev), kobj);
422         struct nvdimm *nvdimm = to_nvdimm(dev);
423
424         if (a != &dev_attr_security.attr && a != &dev_attr_frozen.attr)
425                 return a->mode;
426         if (!nvdimm->sec.flags)
427                 return 0;
428
429         if (a == &dev_attr_security.attr) {
430                 /* Are there any state mutation ops (make writable)? */
431                 if (nvdimm->sec.ops->freeze || nvdimm->sec.ops->disable
432                                 || nvdimm->sec.ops->change_key
433                                 || nvdimm->sec.ops->erase
434                                 || nvdimm->sec.ops->overwrite)
435                         return a->mode;
436                 return 0444;
437         }
438
439         if (nvdimm->sec.ops->freeze)
440                 return a->mode;
441         return 0;
442 }
443
444 static const struct attribute_group nvdimm_attribute_group = {
445         .attrs = nvdimm_attributes,
446         .is_visible = nvdimm_visible,
447 };
448
449 static const struct attribute_group *nvdimm_attribute_groups[] = {
450         &nd_device_attribute_group,
451         &nvdimm_attribute_group,
452         NULL,
453 };
454
455 static const struct device_type nvdimm_device_type = {
456         .name = "nvdimm",
457         .release = nvdimm_release,
458         .groups = nvdimm_attribute_groups,
459 };
460
461 bool is_nvdimm(struct device *dev)
462 {
463         return dev->type == &nvdimm_device_type;
464 }
465
466 struct nvdimm *__nvdimm_create(struct nvdimm_bus *nvdimm_bus,
467                 void *provider_data, const struct attribute_group **groups,
468                 unsigned long flags, unsigned long cmd_mask, int num_flush,
469                 struct resource *flush_wpq, const char *dimm_id,
470                 const struct nvdimm_security_ops *sec_ops)
471 {
472         struct nvdimm *nvdimm = kzalloc(sizeof(*nvdimm), GFP_KERNEL);
473         struct device *dev;
474
475         if (!nvdimm)
476                 return NULL;
477
478         nvdimm->id = ida_simple_get(&dimm_ida, 0, 0, GFP_KERNEL);
479         if (nvdimm->id < 0) {
480                 kfree(nvdimm);
481                 return NULL;
482         }
483
484         nvdimm->dimm_id = dimm_id;
485         nvdimm->provider_data = provider_data;
486         if (noblk)
487                 flags |= 1 << NDD_NOBLK;
488         nvdimm->flags = flags;
489         nvdimm->cmd_mask = cmd_mask;
490         nvdimm->num_flush = num_flush;
491         nvdimm->flush_wpq = flush_wpq;
492         atomic_set(&nvdimm->busy, 0);
493         dev = &nvdimm->dev;
494         dev_set_name(dev, "nmem%d", nvdimm->id);
495         dev->parent = &nvdimm_bus->dev;
496         dev->type = &nvdimm_device_type;
497         dev->devt = MKDEV(nvdimm_major, nvdimm->id);
498         dev->groups = groups;
499         nvdimm->sec.ops = sec_ops;
500         nvdimm->sec.overwrite_tmo = 0;
501         INIT_DELAYED_WORK(&nvdimm->dwork, nvdimm_security_overwrite_query);
502         /*
503          * Security state must be initialized before device_add() for
504          * attribute visibility.
505          */
506         /* get security state and extended (master) state */
507         nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
508         nvdimm->sec.ext_flags = nvdimm_security_flags(nvdimm, NVDIMM_MASTER);
509         nd_device_register(dev);
510
511         return nvdimm;
512 }
513 EXPORT_SYMBOL_GPL(__nvdimm_create);
514
515 static void shutdown_security_notify(void *data)
516 {
517         struct nvdimm *nvdimm = data;
518
519         sysfs_put(nvdimm->sec.overwrite_state);
520 }
521
522 int nvdimm_security_setup_events(struct device *dev)
523 {
524         struct nvdimm *nvdimm = to_nvdimm(dev);
525
526         if (!nvdimm->sec.flags || !nvdimm->sec.ops
527                         || !nvdimm->sec.ops->overwrite)
528                 return 0;
529         nvdimm->sec.overwrite_state = sysfs_get_dirent(dev->kobj.sd, "security");
530         if (!nvdimm->sec.overwrite_state)
531                 return -ENOMEM;
532
533         return devm_add_action_or_reset(dev, shutdown_security_notify, nvdimm);
534 }
535 EXPORT_SYMBOL_GPL(nvdimm_security_setup_events);
536
537 int nvdimm_in_overwrite(struct nvdimm *nvdimm)
538 {
539         return test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags);
540 }
541 EXPORT_SYMBOL_GPL(nvdimm_in_overwrite);
542
543 int nvdimm_security_freeze(struct nvdimm *nvdimm)
544 {
545         int rc;
546
547         WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
548
549         if (!nvdimm->sec.ops || !nvdimm->sec.ops->freeze)
550                 return -EOPNOTSUPP;
551
552         if (!nvdimm->sec.flags)
553                 return -EIO;
554
555         if (test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags)) {
556                 dev_warn(&nvdimm->dev, "Overwrite operation in progress.\n");
557                 return -EBUSY;
558         }
559
560         rc = nvdimm->sec.ops->freeze(nvdimm);
561         nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
562
563         return rc;
564 }
565
566 static unsigned long dpa_align(struct nd_region *nd_region)
567 {
568         struct device *dev = &nd_region->dev;
569
570         if (dev_WARN_ONCE(dev, !is_nvdimm_bus_locked(dev),
571                                 "bus lock required for capacity provision\n"))
572                 return 0;
573         if (dev_WARN_ONCE(dev, !nd_region->ndr_mappings || nd_region->align
574                                 % nd_region->ndr_mappings,
575                                 "invalid region align %#lx mappings: %d\n",
576                                 nd_region->align, nd_region->ndr_mappings))
577                 return 0;
578         return nd_region->align / nd_region->ndr_mappings;
579 }
580
581 int alias_dpa_busy(struct device *dev, void *data)
582 {
583         resource_size_t map_end, blk_start, new;
584         struct blk_alloc_info *info = data;
585         struct nd_mapping *nd_mapping;
586         struct nd_region *nd_region;
587         struct nvdimm_drvdata *ndd;
588         struct resource *res;
589         unsigned long align;
590         int i;
591
592         if (!is_memory(dev))
593                 return 0;
594
595         nd_region = to_nd_region(dev);
596         for (i = 0; i < nd_region->ndr_mappings; i++) {
597                 nd_mapping  = &nd_region->mapping[i];
598                 if (nd_mapping->nvdimm == info->nd_mapping->nvdimm)
599                         break;
600         }
601
602         if (i >= nd_region->ndr_mappings)
603                 return 0;
604
605         ndd = to_ndd(nd_mapping);
606         map_end = nd_mapping->start + nd_mapping->size - 1;
607         blk_start = nd_mapping->start;
608
609         /*
610          * In the allocation case ->res is set to free space that we are
611          * looking to validate against PMEM aliasing collision rules
612          * (i.e. BLK is allocated after all aliased PMEM).
613          */
614         if (info->res) {
615                 if (info->res->start >= nd_mapping->start
616                                 && info->res->start < map_end)
617                         /* pass */;
618                 else
619                         return 0;
620         }
621
622  retry:
623         /*
624          * Find the free dpa from the end of the last pmem allocation to
625          * the end of the interleave-set mapping.
626          */
627         align = dpa_align(nd_region);
628         if (!align)
629                 return 0;
630
631         for_each_dpa_resource(ndd, res) {
632                 resource_size_t start, end;
633
634                 if (strncmp(res->name, "pmem", 4) != 0)
635                         continue;
636
637                 start = ALIGN_DOWN(res->start, align);
638                 end = ALIGN(res->end + 1, align) - 1;
639                 if ((start >= blk_start && start < map_end)
640                                 || (end >= blk_start && end <= map_end)) {
641                         new = max(blk_start, min(map_end, end) + 1);
642                         if (new != blk_start) {
643                                 blk_start = new;
644                                 goto retry;
645                         }
646                 }
647         }
648
649         /* update the free space range with the probed blk_start */
650         if (info->res && blk_start > info->res->start) {
651                 info->res->start = max(info->res->start, blk_start);
652                 if (info->res->start > info->res->end)
653                         info->res->end = info->res->start - 1;
654                 return 1;
655         }
656
657         info->available -= blk_start - nd_mapping->start;
658
659         return 0;
660 }
661
662 /**
663  * nd_blk_available_dpa - account the unused dpa of BLK region
664  * @nd_mapping: container of dpa-resource-root + labels
665  *
666  * Unlike PMEM, BLK namespaces can occupy discontiguous DPA ranges, but
667  * we arrange for them to never start at an lower dpa than the last
668  * PMEM allocation in an aliased region.
669  */
670 resource_size_t nd_blk_available_dpa(struct nd_region *nd_region)
671 {
672         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
673         struct nd_mapping *nd_mapping = &nd_region->mapping[0];
674         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
675         struct blk_alloc_info info = {
676                 .nd_mapping = nd_mapping,
677                 .available = nd_mapping->size,
678                 .res = NULL,
679         };
680         struct resource *res;
681         unsigned long align;
682
683         if (!ndd)
684                 return 0;
685
686         device_for_each_child(&nvdimm_bus->dev, &info, alias_dpa_busy);
687
688         /* now account for busy blk allocations in unaliased dpa */
689         align = dpa_align(nd_region);
690         if (!align)
691                 return 0;
692         for_each_dpa_resource(ndd, res) {
693                 resource_size_t start, end, size;
694
695                 if (strncmp(res->name, "blk", 3) != 0)
696                         continue;
697                 start = ALIGN_DOWN(res->start, align);
698                 end = ALIGN(res->end + 1, align) - 1;
699                 size = end - start + 1;
700                 if (size >= info.available)
701                         return 0;
702                 info.available -= size;
703         }
704
705         return info.available;
706 }
707
708 /**
709  * nd_pmem_max_contiguous_dpa - For the given dimm+region, return the max
710  *                         contiguous unallocated dpa range.
711  * @nd_region: constrain available space check to this reference region
712  * @nd_mapping: container of dpa-resource-root + labels
713  */
714 resource_size_t nd_pmem_max_contiguous_dpa(struct nd_region *nd_region,
715                                            struct nd_mapping *nd_mapping)
716 {
717         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
718         struct nvdimm_bus *nvdimm_bus;
719         resource_size_t max = 0;
720         struct resource *res;
721         unsigned long align;
722
723         /* if a dimm is disabled the available capacity is zero */
724         if (!ndd)
725                 return 0;
726
727         align = dpa_align(nd_region);
728         if (!align)
729                 return 0;
730
731         nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
732         if (__reserve_free_pmem(&nd_region->dev, nd_mapping->nvdimm))
733                 return 0;
734         for_each_dpa_resource(ndd, res) {
735                 resource_size_t start, end;
736
737                 if (strcmp(res->name, "pmem-reserve") != 0)
738                         continue;
739                 /* trim free space relative to current alignment setting */
740                 start = ALIGN(res->start, align);
741                 end = ALIGN_DOWN(res->end + 1, align) - 1;
742                 if (end < start)
743                         continue;
744                 if (end - start + 1 > max)
745                         max = end - start + 1;
746         }
747         release_free_pmem(nvdimm_bus, nd_mapping);
748         return max;
749 }
750
751 /**
752  * nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
753  * @nd_mapping: container of dpa-resource-root + labels
754  * @nd_region: constrain available space check to this reference region
755  * @overlap: calculate available space assuming this level of overlap
756  *
757  * Validate that a PMEM label, if present, aligns with the start of an
758  * interleave set and truncate the available size at the lowest BLK
759  * overlap point.
760  *
761  * The expectation is that this routine is called multiple times as it
762  * probes for the largest BLK encroachment for any single member DIMM of
763  * the interleave set.  Once that value is determined the PMEM-limit for
764  * the set can be established.
765  */
766 resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
767                 struct nd_mapping *nd_mapping, resource_size_t *overlap)
768 {
769         resource_size_t map_start, map_end, busy = 0, available, blk_start;
770         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
771         struct resource *res;
772         const char *reason;
773         unsigned long align;
774
775         if (!ndd)
776                 return 0;
777
778         align = dpa_align(nd_region);
779         if (!align)
780                 return 0;
781
782         map_start = nd_mapping->start;
783         map_end = map_start + nd_mapping->size - 1;
784         blk_start = max(map_start, map_end + 1 - *overlap);
785         for_each_dpa_resource(ndd, res) {
786                 resource_size_t start, end;
787
788                 start = ALIGN_DOWN(res->start, align);
789                 end = ALIGN(res->end + 1, align) - 1;
790                 if (start >= map_start && start < map_end) {
791                         if (strncmp(res->name, "blk", 3) == 0)
792                                 blk_start = min(blk_start,
793                                                 max(map_start, start));
794                         else if (end > map_end) {
795                                 reason = "misaligned to iset";
796                                 goto err;
797                         } else
798                                 busy += end - start + 1;
799                 } else if (end >= map_start && end <= map_end) {
800                         if (strncmp(res->name, "blk", 3) == 0) {
801                                 /*
802                                  * If a BLK allocation overlaps the start of
803                                  * PMEM the entire interleave set may now only
804                                  * be used for BLK.
805                                  */
806                                 blk_start = map_start;
807                         } else
808                                 busy += end - start + 1;
809                 } else if (map_start > start && map_start < end) {
810                         /* total eclipse of the mapping */
811                         busy += nd_mapping->size;
812                         blk_start = map_start;
813                 }
814         }
815
816         *overlap = map_end + 1 - blk_start;
817         available = blk_start - map_start;
818         if (busy < available)
819                 return ALIGN_DOWN(available - busy, align);
820         return 0;
821
822  err:
823         nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
824         return 0;
825 }
826
827 void nvdimm_free_dpa(struct nvdimm_drvdata *ndd, struct resource *res)
828 {
829         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
830         kfree(res->name);
831         __release_region(&ndd->dpa, res->start, resource_size(res));
832 }
833
834 struct resource *nvdimm_allocate_dpa(struct nvdimm_drvdata *ndd,
835                 struct nd_label_id *label_id, resource_size_t start,
836                 resource_size_t n)
837 {
838         char *name = kmemdup(label_id, sizeof(*label_id), GFP_KERNEL);
839         struct resource *res;
840
841         if (!name)
842                 return NULL;
843
844         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
845         res = __request_region(&ndd->dpa, start, n, name, 0);
846         if (!res)
847                 kfree(name);
848         return res;
849 }
850
851 /**
852  * nvdimm_allocated_dpa - sum up the dpa currently allocated to this label_id
853  * @nvdimm: container of dpa-resource-root + labels
854  * @label_id: dpa resource name of the form {pmem|blk}-<human readable uuid>
855  */
856 resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
857                 struct nd_label_id *label_id)
858 {
859         resource_size_t allocated = 0;
860         struct resource *res;
861
862         for_each_dpa_resource(ndd, res)
863                 if (strcmp(res->name, label_id->id) == 0)
864                         allocated += resource_size(res);
865
866         return allocated;
867 }
868
869 static int count_dimms(struct device *dev, void *c)
870 {
871         int *count = c;
872
873         if (is_nvdimm(dev))
874                 (*count)++;
875         return 0;
876 }
877
878 int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count)
879 {
880         int count = 0;
881         /* Flush any possible dimm registration failures */
882         nd_synchronize();
883
884         device_for_each_child(&nvdimm_bus->dev, &count, count_dimms);
885         dev_dbg(&nvdimm_bus->dev, "count: %d\n", count);
886         if (count != dimm_count)
887                 return -ENXIO;
888         return 0;
889 }
890 EXPORT_SYMBOL_GPL(nvdimm_bus_check_dimm_count);
891
892 void __exit nvdimm_devs_exit(void)
893 {
894         ida_destroy(&dimm_ida);
895 }