Merge tag 'drm-misc-fixes-2019-02-07' of git://anongit.freedesktop.org/drm/drm-misc...
[sfrench/cifs-2.6.git] / drivers / nvdimm / dimm_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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/vmalloc.h>
15 #include <linux/device.h>
16 #include <linux/ndctl.h>
17 #include <linux/slab.h>
18 #include <linux/io.h>
19 #include <linux/fs.h>
20 #include <linux/mm.h>
21 #include "nd-core.h"
22 #include "label.h"
23 #include "pmem.h"
24 #include "nd.h"
25
26 static DEFINE_IDA(dimm_ida);
27
28 /*
29  * Retrieve bus and dimm handle and return if this bus supports
30  * get_config_data commands
31  */
32 int nvdimm_check_config_data(struct device *dev)
33 {
34         struct nvdimm *nvdimm = to_nvdimm(dev);
35
36         if (!nvdimm->cmd_mask ||
37             !test_bit(ND_CMD_GET_CONFIG_DATA, &nvdimm->cmd_mask)) {
38                 if (test_bit(NDD_ALIASING, &nvdimm->flags))
39                         return -ENXIO;
40                 else
41                         return -ENOTTY;
42         }
43
44         return 0;
45 }
46
47 static int validate_dimm(struct nvdimm_drvdata *ndd)
48 {
49         int rc;
50
51         if (!ndd)
52                 return -EINVAL;
53
54         rc = nvdimm_check_config_data(ndd->dev);
55         if (rc)
56                 dev_dbg(ndd->dev, "%pf: %s error: %d\n",
57                                 __builtin_return_address(0), __func__, rc);
58         return rc;
59 }
60
61 /**
62  * nvdimm_init_nsarea - determine the geometry of a dimm's namespace area
63  * @nvdimm: dimm to initialize
64  */
65 int nvdimm_init_nsarea(struct nvdimm_drvdata *ndd)
66 {
67         struct nd_cmd_get_config_size *cmd = &ndd->nsarea;
68         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
69         struct nvdimm_bus_descriptor *nd_desc;
70         int rc = validate_dimm(ndd);
71         int cmd_rc = 0;
72
73         if (rc)
74                 return rc;
75
76         if (cmd->config_size)
77                 return 0; /* already valid */
78
79         memset(cmd, 0, sizeof(*cmd));
80         nd_desc = nvdimm_bus->nd_desc;
81         rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
82                         ND_CMD_GET_CONFIG_SIZE, cmd, sizeof(*cmd), &cmd_rc);
83         if (rc < 0)
84                 return rc;
85         return cmd_rc;
86 }
87
88 int nvdimm_get_config_data(struct nvdimm_drvdata *ndd, void *buf,
89                            size_t offset, size_t len)
90 {
91         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
92         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
93         int rc = validate_dimm(ndd), cmd_rc = 0;
94         struct nd_cmd_get_config_data_hdr *cmd;
95         size_t max_cmd_size, buf_offset;
96
97         if (rc)
98                 return rc;
99
100         if (offset + len > ndd->nsarea.config_size)
101                 return -ENXIO;
102
103         max_cmd_size = min_t(u32, len, ndd->nsarea.max_xfer);
104         cmd = kvzalloc(max_cmd_size + sizeof(*cmd), GFP_KERNEL);
105         if (!cmd)
106                 return -ENOMEM;
107
108         for (buf_offset = 0; len;
109              len -= cmd->in_length, buf_offset += cmd->in_length) {
110                 size_t cmd_size;
111
112                 cmd->in_offset = offset + buf_offset;
113                 cmd->in_length = min(max_cmd_size, len);
114
115                 cmd_size = sizeof(*cmd) + cmd->in_length;
116
117                 rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
118                                 ND_CMD_GET_CONFIG_DATA, cmd, cmd_size, &cmd_rc);
119                 if (rc < 0)
120                         break;
121                 if (cmd_rc < 0) {
122                         rc = cmd_rc;
123                         break;
124                 }
125
126                 /* out_buf should be valid, copy it into our output buffer */
127                 memcpy(buf + buf_offset, cmd->out_buf, cmd->in_length);
128         }
129         kvfree(cmd);
130
131         return rc;
132 }
133
134 int nvdimm_set_config_data(struct nvdimm_drvdata *ndd, size_t offset,
135                 void *buf, size_t len)
136 {
137         size_t max_cmd_size, buf_offset;
138         struct nd_cmd_set_config_hdr *cmd;
139         int rc = validate_dimm(ndd), cmd_rc = 0;
140         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
141         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
142
143         if (rc)
144                 return rc;
145
146         if (offset + len > ndd->nsarea.config_size)
147                 return -ENXIO;
148
149         max_cmd_size = min_t(u32, len, ndd->nsarea.max_xfer);
150         cmd = kvzalloc(max_cmd_size + sizeof(*cmd) + sizeof(u32), GFP_KERNEL);
151         if (!cmd)
152                 return -ENOMEM;
153
154         for (buf_offset = 0; len; len -= cmd->in_length,
155                         buf_offset += cmd->in_length) {
156                 size_t cmd_size;
157
158                 cmd->in_offset = offset + buf_offset;
159                 cmd->in_length = min(max_cmd_size, len);
160                 memcpy(cmd->in_buf, buf + buf_offset, cmd->in_length);
161
162                 /* status is output in the last 4-bytes of the command buffer */
163                 cmd_size = sizeof(*cmd) + cmd->in_length + sizeof(u32);
164
165                 rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
166                                 ND_CMD_SET_CONFIG_DATA, cmd, cmd_size, &cmd_rc);
167                 if (rc < 0)
168                         break;
169                 if (cmd_rc < 0) {
170                         rc = cmd_rc;
171                         break;
172                 }
173         }
174         kvfree(cmd);
175
176         return rc;
177 }
178
179 void nvdimm_set_aliasing(struct device *dev)
180 {
181         struct nvdimm *nvdimm = to_nvdimm(dev);
182
183         set_bit(NDD_ALIASING, &nvdimm->flags);
184 }
185
186 void nvdimm_set_locked(struct device *dev)
187 {
188         struct nvdimm *nvdimm = to_nvdimm(dev);
189
190         set_bit(NDD_LOCKED, &nvdimm->flags);
191 }
192
193 void nvdimm_clear_locked(struct device *dev)
194 {
195         struct nvdimm *nvdimm = to_nvdimm(dev);
196
197         clear_bit(NDD_LOCKED, &nvdimm->flags);
198 }
199
200 static void nvdimm_release(struct device *dev)
201 {
202         struct nvdimm *nvdimm = to_nvdimm(dev);
203
204         ida_simple_remove(&dimm_ida, nvdimm->id);
205         kfree(nvdimm);
206 }
207
208 static struct device_type nvdimm_device_type = {
209         .name = "nvdimm",
210         .release = nvdimm_release,
211 };
212
213 bool is_nvdimm(struct device *dev)
214 {
215         return dev->type == &nvdimm_device_type;
216 }
217
218 struct nvdimm *to_nvdimm(struct device *dev)
219 {
220         struct nvdimm *nvdimm = container_of(dev, struct nvdimm, dev);
221
222         WARN_ON(!is_nvdimm(dev));
223         return nvdimm;
224 }
225 EXPORT_SYMBOL_GPL(to_nvdimm);
226
227 struct nvdimm *nd_blk_region_to_dimm(struct nd_blk_region *ndbr)
228 {
229         struct nd_region *nd_region = &ndbr->nd_region;
230         struct nd_mapping *nd_mapping = &nd_region->mapping[0];
231
232         return nd_mapping->nvdimm;
233 }
234 EXPORT_SYMBOL_GPL(nd_blk_region_to_dimm);
235
236 unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr)
237 {
238         /* pmem mapping properties are private to libnvdimm */
239         return ARCH_MEMREMAP_PMEM;
240 }
241 EXPORT_SYMBOL_GPL(nd_blk_memremap_flags);
242
243 struct nvdimm_drvdata *to_ndd(struct nd_mapping *nd_mapping)
244 {
245         struct nvdimm *nvdimm = nd_mapping->nvdimm;
246
247         WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
248
249         return dev_get_drvdata(&nvdimm->dev);
250 }
251 EXPORT_SYMBOL(to_ndd);
252
253 void nvdimm_drvdata_release(struct kref *kref)
254 {
255         struct nvdimm_drvdata *ndd = container_of(kref, typeof(*ndd), kref);
256         struct device *dev = ndd->dev;
257         struct resource *res, *_r;
258
259         dev_dbg(dev, "trace\n");
260         nvdimm_bus_lock(dev);
261         for_each_dpa_resource_safe(ndd, res, _r)
262                 nvdimm_free_dpa(ndd, res);
263         nvdimm_bus_unlock(dev);
264
265         kvfree(ndd->data);
266         kfree(ndd);
267         put_device(dev);
268 }
269
270 void get_ndd(struct nvdimm_drvdata *ndd)
271 {
272         kref_get(&ndd->kref);
273 }
274
275 void put_ndd(struct nvdimm_drvdata *ndd)
276 {
277         if (ndd)
278                 kref_put(&ndd->kref, nvdimm_drvdata_release);
279 }
280
281 const char *nvdimm_name(struct nvdimm *nvdimm)
282 {
283         return dev_name(&nvdimm->dev);
284 }
285 EXPORT_SYMBOL_GPL(nvdimm_name);
286
287 struct kobject *nvdimm_kobj(struct nvdimm *nvdimm)
288 {
289         return &nvdimm->dev.kobj;
290 }
291 EXPORT_SYMBOL_GPL(nvdimm_kobj);
292
293 unsigned long nvdimm_cmd_mask(struct nvdimm *nvdimm)
294 {
295         return nvdimm->cmd_mask;
296 }
297 EXPORT_SYMBOL_GPL(nvdimm_cmd_mask);
298
299 void *nvdimm_provider_data(struct nvdimm *nvdimm)
300 {
301         if (nvdimm)
302                 return nvdimm->provider_data;
303         return NULL;
304 }
305 EXPORT_SYMBOL_GPL(nvdimm_provider_data);
306
307 static ssize_t commands_show(struct device *dev,
308                 struct device_attribute *attr, char *buf)
309 {
310         struct nvdimm *nvdimm = to_nvdimm(dev);
311         int cmd, len = 0;
312
313         if (!nvdimm->cmd_mask)
314                 return sprintf(buf, "\n");
315
316         for_each_set_bit(cmd, &nvdimm->cmd_mask, BITS_PER_LONG)
317                 len += sprintf(buf + len, "%s ", nvdimm_cmd_name(cmd));
318         len += sprintf(buf + len, "\n");
319         return len;
320 }
321 static DEVICE_ATTR_RO(commands);
322
323 static ssize_t flags_show(struct device *dev,
324                 struct device_attribute *attr, char *buf)
325 {
326         struct nvdimm *nvdimm = to_nvdimm(dev);
327
328         return sprintf(buf, "%s%s\n",
329                         test_bit(NDD_ALIASING, &nvdimm->flags) ? "alias " : "",
330                         test_bit(NDD_LOCKED, &nvdimm->flags) ? "lock " : "");
331 }
332 static DEVICE_ATTR_RO(flags);
333
334 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
335                 char *buf)
336 {
337         struct nvdimm *nvdimm = to_nvdimm(dev);
338
339         /*
340          * The state may be in the process of changing, userspace should
341          * quiesce probing if it wants a static answer
342          */
343         nvdimm_bus_lock(dev);
344         nvdimm_bus_unlock(dev);
345         return sprintf(buf, "%s\n", atomic_read(&nvdimm->busy)
346                         ? "active" : "idle");
347 }
348 static DEVICE_ATTR_RO(state);
349
350 static ssize_t available_slots_show(struct device *dev,
351                 struct device_attribute *attr, char *buf)
352 {
353         struct nvdimm_drvdata *ndd = dev_get_drvdata(dev);
354         ssize_t rc;
355         u32 nfree;
356
357         if (!ndd)
358                 return -ENXIO;
359
360         nvdimm_bus_lock(dev);
361         nfree = nd_label_nfree(ndd);
362         if (nfree - 1 > nfree) {
363                 dev_WARN_ONCE(dev, 1, "we ate our last label?\n");
364                 nfree = 0;
365         } else
366                 nfree--;
367         rc = sprintf(buf, "%d\n", nfree);
368         nvdimm_bus_unlock(dev);
369         return rc;
370 }
371 static DEVICE_ATTR_RO(available_slots);
372
373 __weak ssize_t security_show(struct device *dev,
374                 struct device_attribute *attr, char *buf)
375 {
376         struct nvdimm *nvdimm = to_nvdimm(dev);
377
378         switch (nvdimm->sec.state) {
379         case NVDIMM_SECURITY_DISABLED:
380                 return sprintf(buf, "disabled\n");
381         case NVDIMM_SECURITY_UNLOCKED:
382                 return sprintf(buf, "unlocked\n");
383         case NVDIMM_SECURITY_LOCKED:
384                 return sprintf(buf, "locked\n");
385         case NVDIMM_SECURITY_FROZEN:
386                 return sprintf(buf, "frozen\n");
387         case NVDIMM_SECURITY_OVERWRITE:
388                 return sprintf(buf, "overwrite\n");
389         default:
390                 return -ENOTTY;
391         }
392
393         return -ENOTTY;
394 }
395
396 #define OPS                                                     \
397         C( OP_FREEZE,           "freeze",               1),     \
398         C( OP_DISABLE,          "disable",              2),     \
399         C( OP_UPDATE,           "update",               3),     \
400         C( OP_ERASE,            "erase",                2),     \
401         C( OP_OVERWRITE,        "overwrite",            2),     \
402         C( OP_MASTER_UPDATE,    "master_update",        3),     \
403         C( OP_MASTER_ERASE,     "master_erase",         2)
404 #undef C
405 #define C(a, b, c) a
406 enum nvdimmsec_op_ids { OPS };
407 #undef C
408 #define C(a, b, c) { b, c }
409 static struct {
410         const char *name;
411         int args;
412 } ops[] = { OPS };
413 #undef C
414
415 #define SEC_CMD_SIZE 32
416 #define KEY_ID_SIZE 10
417
418 static ssize_t __security_store(struct device *dev, const char *buf, size_t len)
419 {
420         struct nvdimm *nvdimm = to_nvdimm(dev);
421         ssize_t rc;
422         char cmd[SEC_CMD_SIZE+1], keystr[KEY_ID_SIZE+1],
423                 nkeystr[KEY_ID_SIZE+1];
424         unsigned int key, newkey;
425         int i;
426
427         if (atomic_read(&nvdimm->busy))
428                 return -EBUSY;
429
430         rc = sscanf(buf, "%"__stringify(SEC_CMD_SIZE)"s"
431                         " %"__stringify(KEY_ID_SIZE)"s"
432                         " %"__stringify(KEY_ID_SIZE)"s",
433                         cmd, keystr, nkeystr);
434         if (rc < 1)
435                 return -EINVAL;
436         for (i = 0; i < ARRAY_SIZE(ops); i++)
437                 if (sysfs_streq(cmd, ops[i].name))
438                         break;
439         if (i >= ARRAY_SIZE(ops))
440                 return -EINVAL;
441         if (ops[i].args > 1)
442                 rc = kstrtouint(keystr, 0, &key);
443         if (rc >= 0 && ops[i].args > 2)
444                 rc = kstrtouint(nkeystr, 0, &newkey);
445         if (rc < 0)
446                 return rc;
447
448         if (i == OP_FREEZE) {
449                 dev_dbg(dev, "freeze\n");
450                 rc = nvdimm_security_freeze(nvdimm);
451         } else if (i == OP_DISABLE) {
452                 dev_dbg(dev, "disable %u\n", key);
453                 rc = nvdimm_security_disable(nvdimm, key);
454         } else if (i == OP_UPDATE) {
455                 dev_dbg(dev, "update %u %u\n", key, newkey);
456                 rc = nvdimm_security_update(nvdimm, key, newkey, NVDIMM_USER);
457         } else if (i == OP_ERASE) {
458                 dev_dbg(dev, "erase %u\n", key);
459                 rc = nvdimm_security_erase(nvdimm, key, NVDIMM_USER);
460         } else if (i == OP_OVERWRITE) {
461                 dev_dbg(dev, "overwrite %u\n", key);
462                 rc = nvdimm_security_overwrite(nvdimm, key);
463         } else if (i == OP_MASTER_UPDATE) {
464                 dev_dbg(dev, "master_update %u %u\n", key, newkey);
465                 rc = nvdimm_security_update(nvdimm, key, newkey,
466                                 NVDIMM_MASTER);
467         } else if (i == OP_MASTER_ERASE) {
468                 dev_dbg(dev, "master_erase %u\n", key);
469                 rc = nvdimm_security_erase(nvdimm, key,
470                                 NVDIMM_MASTER);
471         } else
472                 return -EINVAL;
473
474         if (rc == 0)
475                 rc = len;
476         return rc;
477 }
478
479 static ssize_t security_store(struct device *dev,
480                 struct device_attribute *attr, const char *buf, size_t len)
481
482 {
483         ssize_t rc;
484
485         /*
486          * Require all userspace triggered security management to be
487          * done while probing is idle and the DIMM is not in active use
488          * in any region.
489          */
490         device_lock(dev);
491         nvdimm_bus_lock(dev);
492         wait_nvdimm_bus_probe_idle(dev);
493         rc = __security_store(dev, buf, len);
494         nvdimm_bus_unlock(dev);
495         device_unlock(dev);
496
497         return rc;
498 }
499 static DEVICE_ATTR_RW(security);
500
501 static struct attribute *nvdimm_attributes[] = {
502         &dev_attr_state.attr,
503         &dev_attr_flags.attr,
504         &dev_attr_commands.attr,
505         &dev_attr_available_slots.attr,
506         &dev_attr_security.attr,
507         NULL,
508 };
509
510 static umode_t nvdimm_visible(struct kobject *kobj, struct attribute *a, int n)
511 {
512         struct device *dev = container_of(kobj, typeof(*dev), kobj);
513         struct nvdimm *nvdimm = to_nvdimm(dev);
514
515         if (a != &dev_attr_security.attr)
516                 return a->mode;
517         if (nvdimm->sec.state < 0)
518                 return 0;
519         /* Are there any state mutation ops? */
520         if (nvdimm->sec.ops->freeze || nvdimm->sec.ops->disable
521                         || nvdimm->sec.ops->change_key
522                         || nvdimm->sec.ops->erase
523                         || nvdimm->sec.ops->overwrite)
524                 return a->mode;
525         return 0444;
526 }
527
528 struct attribute_group nvdimm_attribute_group = {
529         .attrs = nvdimm_attributes,
530         .is_visible = nvdimm_visible,
531 };
532 EXPORT_SYMBOL_GPL(nvdimm_attribute_group);
533
534 struct nvdimm *__nvdimm_create(struct nvdimm_bus *nvdimm_bus,
535                 void *provider_data, const struct attribute_group **groups,
536                 unsigned long flags, unsigned long cmd_mask, int num_flush,
537                 struct resource *flush_wpq, const char *dimm_id,
538                 const struct nvdimm_security_ops *sec_ops)
539 {
540         struct nvdimm *nvdimm = kzalloc(sizeof(*nvdimm), GFP_KERNEL);
541         struct device *dev;
542
543         if (!nvdimm)
544                 return NULL;
545
546         nvdimm->id = ida_simple_get(&dimm_ida, 0, 0, GFP_KERNEL);
547         if (nvdimm->id < 0) {
548                 kfree(nvdimm);
549                 return NULL;
550         }
551
552         nvdimm->dimm_id = dimm_id;
553         nvdimm->provider_data = provider_data;
554         nvdimm->flags = flags;
555         nvdimm->cmd_mask = cmd_mask;
556         nvdimm->num_flush = num_flush;
557         nvdimm->flush_wpq = flush_wpq;
558         atomic_set(&nvdimm->busy, 0);
559         dev = &nvdimm->dev;
560         dev_set_name(dev, "nmem%d", nvdimm->id);
561         dev->parent = &nvdimm_bus->dev;
562         dev->type = &nvdimm_device_type;
563         dev->devt = MKDEV(nvdimm_major, nvdimm->id);
564         dev->groups = groups;
565         nvdimm->sec.ops = sec_ops;
566         nvdimm->sec.overwrite_tmo = 0;
567         INIT_DELAYED_WORK(&nvdimm->dwork, nvdimm_security_overwrite_query);
568         /*
569          * Security state must be initialized before device_add() for
570          * attribute visibility.
571          */
572         /* get security state and extended (master) state */
573         nvdimm->sec.state = nvdimm_security_state(nvdimm, NVDIMM_USER);
574         nvdimm->sec.ext_state = nvdimm_security_state(nvdimm, NVDIMM_MASTER);
575         nd_device_register(dev);
576
577         return nvdimm;
578 }
579 EXPORT_SYMBOL_GPL(__nvdimm_create);
580
581 static void shutdown_security_notify(void *data)
582 {
583         struct nvdimm *nvdimm = data;
584
585         sysfs_put(nvdimm->sec.overwrite_state);
586 }
587
588 int nvdimm_security_setup_events(struct device *dev)
589 {
590         struct nvdimm *nvdimm = to_nvdimm(dev);
591
592         if (nvdimm->sec.state < 0 || !nvdimm->sec.ops
593                         || !nvdimm->sec.ops->overwrite)
594                 return 0;
595         nvdimm->sec.overwrite_state = sysfs_get_dirent(dev->kobj.sd, "security");
596         if (!nvdimm->sec.overwrite_state)
597                 return -ENOMEM;
598
599         return devm_add_action_or_reset(dev, shutdown_security_notify, nvdimm);
600 }
601 EXPORT_SYMBOL_GPL(nvdimm_security_setup_events);
602
603 int nvdimm_in_overwrite(struct nvdimm *nvdimm)
604 {
605         return test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags);
606 }
607 EXPORT_SYMBOL_GPL(nvdimm_in_overwrite);
608
609 int nvdimm_security_freeze(struct nvdimm *nvdimm)
610 {
611         int rc;
612
613         WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
614
615         if (!nvdimm->sec.ops || !nvdimm->sec.ops->freeze)
616                 return -EOPNOTSUPP;
617
618         if (nvdimm->sec.state < 0)
619                 return -EIO;
620
621         if (test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags)) {
622                 dev_warn(&nvdimm->dev, "Overwrite operation in progress.\n");
623                 return -EBUSY;
624         }
625
626         rc = nvdimm->sec.ops->freeze(nvdimm);
627         nvdimm->sec.state = nvdimm_security_state(nvdimm, NVDIMM_USER);
628
629         return rc;
630 }
631
632 int alias_dpa_busy(struct device *dev, void *data)
633 {
634         resource_size_t map_end, blk_start, new;
635         struct blk_alloc_info *info = data;
636         struct nd_mapping *nd_mapping;
637         struct nd_region *nd_region;
638         struct nvdimm_drvdata *ndd;
639         struct resource *res;
640         int i;
641
642         if (!is_memory(dev))
643                 return 0;
644
645         nd_region = to_nd_region(dev);
646         for (i = 0; i < nd_region->ndr_mappings; i++) {
647                 nd_mapping  = &nd_region->mapping[i];
648                 if (nd_mapping->nvdimm == info->nd_mapping->nvdimm)
649                         break;
650         }
651
652         if (i >= nd_region->ndr_mappings)
653                 return 0;
654
655         ndd = to_ndd(nd_mapping);
656         map_end = nd_mapping->start + nd_mapping->size - 1;
657         blk_start = nd_mapping->start;
658
659         /*
660          * In the allocation case ->res is set to free space that we are
661          * looking to validate against PMEM aliasing collision rules
662          * (i.e. BLK is allocated after all aliased PMEM).
663          */
664         if (info->res) {
665                 if (info->res->start >= nd_mapping->start
666                                 && info->res->start < map_end)
667                         /* pass */;
668                 else
669                         return 0;
670         }
671
672  retry:
673         /*
674          * Find the free dpa from the end of the last pmem allocation to
675          * the end of the interleave-set mapping.
676          */
677         for_each_dpa_resource(ndd, res) {
678                 if (strncmp(res->name, "pmem", 4) != 0)
679                         continue;
680                 if ((res->start >= blk_start && res->start < map_end)
681                                 || (res->end >= blk_start
682                                         && res->end <= map_end)) {
683                         new = max(blk_start, min(map_end + 1, res->end + 1));
684                         if (new != blk_start) {
685                                 blk_start = new;
686                                 goto retry;
687                         }
688                 }
689         }
690
691         /* update the free space range with the probed blk_start */
692         if (info->res && blk_start > info->res->start) {
693                 info->res->start = max(info->res->start, blk_start);
694                 if (info->res->start > info->res->end)
695                         info->res->end = info->res->start - 1;
696                 return 1;
697         }
698
699         info->available -= blk_start - nd_mapping->start;
700
701         return 0;
702 }
703
704 /**
705  * nd_blk_available_dpa - account the unused dpa of BLK region
706  * @nd_mapping: container of dpa-resource-root + labels
707  *
708  * Unlike PMEM, BLK namespaces can occupy discontiguous DPA ranges, but
709  * we arrange for them to never start at an lower dpa than the last
710  * PMEM allocation in an aliased region.
711  */
712 resource_size_t nd_blk_available_dpa(struct nd_region *nd_region)
713 {
714         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
715         struct nd_mapping *nd_mapping = &nd_region->mapping[0];
716         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
717         struct blk_alloc_info info = {
718                 .nd_mapping = nd_mapping,
719                 .available = nd_mapping->size,
720                 .res = NULL,
721         };
722         struct resource *res;
723
724         if (!ndd)
725                 return 0;
726
727         device_for_each_child(&nvdimm_bus->dev, &info, alias_dpa_busy);
728
729         /* now account for busy blk allocations in unaliased dpa */
730         for_each_dpa_resource(ndd, res) {
731                 if (strncmp(res->name, "blk", 3) != 0)
732                         continue;
733                 info.available -= resource_size(res);
734         }
735
736         return info.available;
737 }
738
739 /**
740  * nd_pmem_max_contiguous_dpa - For the given dimm+region, return the max
741  *                         contiguous unallocated dpa range.
742  * @nd_region: constrain available space check to this reference region
743  * @nd_mapping: container of dpa-resource-root + labels
744  */
745 resource_size_t nd_pmem_max_contiguous_dpa(struct nd_region *nd_region,
746                                            struct nd_mapping *nd_mapping)
747 {
748         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
749         struct nvdimm_bus *nvdimm_bus;
750         resource_size_t max = 0;
751         struct resource *res;
752
753         /* if a dimm is disabled the available capacity is zero */
754         if (!ndd)
755                 return 0;
756
757         nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
758         if (__reserve_free_pmem(&nd_region->dev, nd_mapping->nvdimm))
759                 return 0;
760         for_each_dpa_resource(ndd, res) {
761                 if (strcmp(res->name, "pmem-reserve") != 0)
762                         continue;
763                 if (resource_size(res) > max)
764                         max = resource_size(res);
765         }
766         release_free_pmem(nvdimm_bus, nd_mapping);
767         return max;
768 }
769
770 /**
771  * nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
772  * @nd_mapping: container of dpa-resource-root + labels
773  * @nd_region: constrain available space check to this reference region
774  * @overlap: calculate available space assuming this level of overlap
775  *
776  * Validate that a PMEM label, if present, aligns with the start of an
777  * interleave set and truncate the available size at the lowest BLK
778  * overlap point.
779  *
780  * The expectation is that this routine is called multiple times as it
781  * probes for the largest BLK encroachment for any single member DIMM of
782  * the interleave set.  Once that value is determined the PMEM-limit for
783  * the set can be established.
784  */
785 resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
786                 struct nd_mapping *nd_mapping, resource_size_t *overlap)
787 {
788         resource_size_t map_start, map_end, busy = 0, available, blk_start;
789         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
790         struct resource *res;
791         const char *reason;
792
793         if (!ndd)
794                 return 0;
795
796         map_start = nd_mapping->start;
797         map_end = map_start + nd_mapping->size - 1;
798         blk_start = max(map_start, map_end + 1 - *overlap);
799         for_each_dpa_resource(ndd, res) {
800                 if (res->start >= map_start && res->start < map_end) {
801                         if (strncmp(res->name, "blk", 3) == 0)
802                                 blk_start = min(blk_start,
803                                                 max(map_start, res->start));
804                         else if (res->end > map_end) {
805                                 reason = "misaligned to iset";
806                                 goto err;
807                         } else
808                                 busy += resource_size(res);
809                 } else if (res->end >= map_start && res->end <= map_end) {
810                         if (strncmp(res->name, "blk", 3) == 0) {
811                                 /*
812                                  * If a BLK allocation overlaps the start of
813                                  * PMEM the entire interleave set may now only
814                                  * be used for BLK.
815                                  */
816                                 blk_start = map_start;
817                         } else
818                                 busy += resource_size(res);
819                 } else if (map_start > res->start && map_start < res->end) {
820                         /* total eclipse of the mapping */
821                         busy += nd_mapping->size;
822                         blk_start = map_start;
823                 }
824         }
825
826         *overlap = map_end + 1 - blk_start;
827         available = blk_start - map_start;
828         if (busy < available)
829                 return available - busy;
830         return 0;
831
832  err:
833         nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
834         return 0;
835 }
836
837 void nvdimm_free_dpa(struct nvdimm_drvdata *ndd, struct resource *res)
838 {
839         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
840         kfree(res->name);
841         __release_region(&ndd->dpa, res->start, resource_size(res));
842 }
843
844 struct resource *nvdimm_allocate_dpa(struct nvdimm_drvdata *ndd,
845                 struct nd_label_id *label_id, resource_size_t start,
846                 resource_size_t n)
847 {
848         char *name = kmemdup(label_id, sizeof(*label_id), GFP_KERNEL);
849         struct resource *res;
850
851         if (!name)
852                 return NULL;
853
854         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
855         res = __request_region(&ndd->dpa, start, n, name, 0);
856         if (!res)
857                 kfree(name);
858         return res;
859 }
860
861 /**
862  * nvdimm_allocated_dpa - sum up the dpa currently allocated to this label_id
863  * @nvdimm: container of dpa-resource-root + labels
864  * @label_id: dpa resource name of the form {pmem|blk}-<human readable uuid>
865  */
866 resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
867                 struct nd_label_id *label_id)
868 {
869         resource_size_t allocated = 0;
870         struct resource *res;
871
872         for_each_dpa_resource(ndd, res)
873                 if (strcmp(res->name, label_id->id) == 0)
874                         allocated += resource_size(res);
875
876         return allocated;
877 }
878
879 static int count_dimms(struct device *dev, void *c)
880 {
881         int *count = c;
882
883         if (is_nvdimm(dev))
884                 (*count)++;
885         return 0;
886 }
887
888 int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count)
889 {
890         int count = 0;
891         /* Flush any possible dimm registration failures */
892         nd_synchronize();
893
894         device_for_each_child(&nvdimm_bus->dev, &count, count_dimms);
895         dev_dbg(&nvdimm_bus->dev, "count: %d\n", count);
896         if (count != dimm_count)
897                 return -ENXIO;
898         return 0;
899 }
900 EXPORT_SYMBOL_GPL(nvdimm_bus_check_dimm_count);
901
902 void __exit nvdimm_devs_exit(void)
903 {
904         ida_destroy(&dimm_ida);
905 }