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_init_config_data(struct nvdimm_drvdata *ndd)
  89 {
  90         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
  91         int rc = validate_dimm(ndd), cmd_rc = 0;
  92         struct nd_cmd_get_config_data_hdr *cmd;
  93         struct nvdimm_bus_descriptor *nd_desc;
  94         u32 max_cmd_size, config_size;
  95         size_t offset;
  96
  97         if (rc)
  98                 return rc;
  99
 100         if (ndd->data)
 101                 return 0;
 102
 103         if (ndd->nsarea.status || ndd->nsarea.max_xfer == 0
 104                         || ndd->nsarea.config_size < ND_LABEL_MIN_SIZE) {
 105                 dev_dbg(ndd->dev, "failed to init config data area: (%d:%d)\n",
 106                                 ndd->nsarea.max_xfer, ndd->nsarea.config_size);
 107                 return -ENXIO;
 108         }
 109
 110         ndd->data = kvmalloc(ndd->nsarea.config_size, GFP_KERNEL);
 111         if (!ndd->data)
 112                 return -ENOMEM;
 113
 114         max_cmd_size = min_t(u32, PAGE_SIZE, ndd->nsarea.max_xfer);
 115         cmd = kzalloc(max_cmd_size + sizeof(*cmd), GFP_KERNEL);
 116         if (!cmd)
 117                 return -ENOMEM;
 118
 119         nd_desc = nvdimm_bus->nd_desc;
 120         for (config_size = ndd->nsarea.config_size, offset = 0;
 121                         config_size; config_size -= cmd->in_length,
 122                         offset += cmd->in_length) {
 123                 cmd->in_length = min(config_size, max_cmd_size);
 124                 cmd->in_offset = offset;
 125                 rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
 126                                 ND_CMD_GET_CONFIG_DATA, cmd,
 127                                 cmd->in_length + sizeof(*cmd), &cmd_rc);
 128                 if (rc < 0)
 129                         break;
 130                 if (cmd_rc < 0) {
 131                         rc = cmd_rc;
 132                         break;
 133                 }
 134                 memcpy(ndd->data + offset, cmd->out_buf, cmd->in_length);
 135         }
 136         dev_dbg(ndd->dev, "len: %zu rc: %d\n", offset, rc);
 137         kfree(cmd);
 138
 139         return rc;
 140 }
 141
 142 int nvdimm_set_config_data(struct nvdimm_drvdata *ndd, size_t offset,
 143                 void *buf, size_t len)
 144 {
 145         size_t max_cmd_size, buf_offset;
 146         struct nd_cmd_set_config_hdr *cmd;
 147         int rc = validate_dimm(ndd), cmd_rc = 0;
 148         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
 149         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
 150
 151         if (rc)
 152                 return rc;
 153
 154         if (!ndd->data)
 155                 return -ENXIO;
 156
 157         if (offset + len > ndd->nsarea.config_size)
 158                 return -ENXIO;
 159
 160         max_cmd_size = min_t(u32, PAGE_SIZE, len);
 161         max_cmd_size = min_t(u32, max_cmd_size, ndd->nsarea.max_xfer);
 162         cmd = kzalloc(max_cmd_size + sizeof(*cmd) + sizeof(u32), GFP_KERNEL);
 163         if (!cmd)
 164                 return -ENOMEM;
 165
 166         for (buf_offset = 0; len; len -= cmd->in_length,
 167                         buf_offset += cmd->in_length) {
 168                 size_t cmd_size;
 169
 170                 cmd->in_offset = offset + buf_offset;
 171                 cmd->in_length = min(max_cmd_size, len);
 172                 memcpy(cmd->in_buf, buf + buf_offset, cmd->in_length);
 173
 174                 /* status is output in the last 4-bytes of the command buffer */
 175                 cmd_size = sizeof(*cmd) + cmd->in_length + sizeof(u32);
 176
 177                 rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
 178                                 ND_CMD_SET_CONFIG_DATA, cmd, cmd_size, &cmd_rc);
 179                 if (rc < 0)
 180                         break;
 181                 if (cmd_rc < 0) {
 182                         rc = cmd_rc;
 183                         break;
 184                 }
 185         }
 186         kfree(cmd);
 187
 188         return rc;
 189 }
 190
 191 void nvdimm_set_aliasing(struct device *dev)
 192 {
 193         struct nvdimm *nvdimm = to_nvdimm(dev);
 194
 195         set_bit(NDD_ALIASING, &nvdimm->flags);
 196 }
 197
 198 void nvdimm_set_locked(struct device *dev)
 199 {
 200         struct nvdimm *nvdimm = to_nvdimm(dev);
 201
 202         set_bit(NDD_LOCKED, &nvdimm->flags);
 203 }
 204
 205 void nvdimm_clear_locked(struct device *dev)
 206 {
 207         struct nvdimm *nvdimm = to_nvdimm(dev);
 208
 209         clear_bit(NDD_LOCKED, &nvdimm->flags);
 210 }
 211
 212 static void nvdimm_release(struct device *dev)
 213 {
 214         struct nvdimm *nvdimm = to_nvdimm(dev);
 215
 216         ida_simple_remove(&dimm_ida, nvdimm->id);
 217         kfree(nvdimm);
 218 }
 219
 220 static struct device_type nvdimm_device_type = {
 221         .name = "nvdimm",
 222         .release = nvdimm_release,
 223 };
 224
 225 bool is_nvdimm(struct device *dev)
 226 {
 227         return dev->type == &nvdimm_device_type;
 228 }
 229
 230 struct nvdimm *to_nvdimm(struct device *dev)
 231 {
 232         struct nvdimm *nvdimm = container_of(dev, struct nvdimm, dev);
 233
 234         WARN_ON(!is_nvdimm(dev));
 235         return nvdimm;
 236 }
 237 EXPORT_SYMBOL_GPL(to_nvdimm);
 238
 239 struct nvdimm *nd_blk_region_to_dimm(struct nd_blk_region *ndbr)
 240 {
 241         struct nd_region *nd_region = &ndbr->nd_region;
 242         struct nd_mapping *nd_mapping = &nd_region->mapping[0];
 243
 244         return nd_mapping->nvdimm;
 245 }
 246 EXPORT_SYMBOL_GPL(nd_blk_region_to_dimm);
 247
 248 unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr)
 249 {
 250         /* pmem mapping properties are private to libnvdimm */
 251         return ARCH_MEMREMAP_PMEM;
 252 }
 253 EXPORT_SYMBOL_GPL(nd_blk_memremap_flags);
 254
 255 struct nvdimm_drvdata *to_ndd(struct nd_mapping *nd_mapping)
 256 {
 257         struct nvdimm *nvdimm = nd_mapping->nvdimm;
 258
 259         WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
 260
 261         return dev_get_drvdata(&nvdimm->dev);
 262 }
 263 EXPORT_SYMBOL(to_ndd);
 264
 265 void nvdimm_drvdata_release(struct kref *kref)
 266 {
 267         struct nvdimm_drvdata *ndd = container_of(kref, typeof(*ndd), kref);
 268         struct device *dev = ndd->dev;
 269         struct resource *res, *_r;
 270
 271         dev_dbg(dev, "trace\n");
 272         nvdimm_bus_lock(dev);
 273         for_each_dpa_resource_safe(ndd, res, _r)
 274                 nvdimm_free_dpa(ndd, res);
 275         nvdimm_bus_unlock(dev);
 276
 277         kvfree(ndd->data);
 278         kfree(ndd);
 279         put_device(dev);
 280 }
 281
 282 void get_ndd(struct nvdimm_drvdata *ndd)
 283 {
 284         kref_get(&ndd->kref);
 285 }
 286
 287 void put_ndd(struct nvdimm_drvdata *ndd)
 288 {
 289         if (ndd)
 290                 kref_put(&ndd->kref, nvdimm_drvdata_release);
 291 }
 292
 293 const char *nvdimm_name(struct nvdimm *nvdimm)
 294 {
 295         return dev_name(&nvdimm->dev);
 296 }
 297 EXPORT_SYMBOL_GPL(nvdimm_name);
 298
 299 struct kobject *nvdimm_kobj(struct nvdimm *nvdimm)
 300 {
 301         return &nvdimm->dev.kobj;
 302 }
 303 EXPORT_SYMBOL_GPL(nvdimm_kobj);
 304
 305 unsigned long nvdimm_cmd_mask(struct nvdimm *nvdimm)
 306 {
 307         return nvdimm->cmd_mask;
 308 }
 309 EXPORT_SYMBOL_GPL(nvdimm_cmd_mask);
 310
 311 void *nvdimm_provider_data(struct nvdimm *nvdimm)
 312 {
 313         if (nvdimm)
 314                 return nvdimm->provider_data;
 315         return NULL;
 316 }
 317 EXPORT_SYMBOL_GPL(nvdimm_provider_data);
 318
 319 static ssize_t commands_show(struct device *dev,
 320                 struct device_attribute *attr, char *buf)
 321 {
 322         struct nvdimm *nvdimm = to_nvdimm(dev);
 323         int cmd, len = 0;
 324
 325         if (!nvdimm->cmd_mask)
 326                 return sprintf(buf, "\n");
 327
 328         for_each_set_bit(cmd, &nvdimm->cmd_mask, BITS_PER_LONG)
 329                 len += sprintf(buf + len, "%s ", nvdimm_cmd_name(cmd));
 330         len += sprintf(buf + len, "\n");
 331         return len;
 332 }
 333 static DEVICE_ATTR_RO(commands);
 334
 335 static ssize_t flags_show(struct device *dev,
 336                 struct device_attribute *attr, char *buf)
 337 {
 338         struct nvdimm *nvdimm = to_nvdimm(dev);
 339
 340         return sprintf(buf, "%s%s\n",
 341                         test_bit(NDD_ALIASING, &nvdimm->flags) ? "alias " : "",
 342                         test_bit(NDD_LOCKED, &nvdimm->flags) ? "lock " : "");
 343 }
 344 static DEVICE_ATTR_RO(flags);
 345
 346 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 347                 char *buf)
 348 {
 349         struct nvdimm *nvdimm = to_nvdimm(dev);
 350
 351         /*
 352          * The state may be in the process of changing, userspace should
 353          * quiesce probing if it wants a static answer
 354          */
 355         nvdimm_bus_lock(dev);
 356         nvdimm_bus_unlock(dev);
 357         return sprintf(buf, "%s\n", atomic_read(&nvdimm->busy)
 358                         ? "active" : "idle");
 359 }
 360 static DEVICE_ATTR_RO(state);
 361
 362 static ssize_t available_slots_show(struct device *dev,
 363                 struct device_attribute *attr, char *buf)
 364 {
 365         struct nvdimm_drvdata *ndd = dev_get_drvdata(dev);
 366         ssize_t rc;
 367         u32 nfree;
 368
 369         if (!ndd)
 370                 return -ENXIO;
 371
 372         nvdimm_bus_lock(dev);
 373         nfree = nd_label_nfree(ndd);
 374         if (nfree - 1 > nfree) {
 375                 dev_WARN_ONCE(dev, 1, "we ate our last label?\n");
 376                 nfree = 0;
 377         } else
 378                 nfree--;
 379         rc = sprintf(buf, "%d\n", nfree);
 380         nvdimm_bus_unlock(dev);
 381         return rc;
 382 }
 383 static DEVICE_ATTR_RO(available_slots);
 384
 385 static struct attribute *nvdimm_attributes[] = {
 386         &dev_attr_state.attr,
 387         &dev_attr_flags.attr,
 388         &dev_attr_commands.attr,
 389         &dev_attr_available_slots.attr,
 390         NULL,
 391 };
 392
 393 struct attribute_group nvdimm_attribute_group = {
 394         .attrs = nvdimm_attributes,
 395 };
 396 EXPORT_SYMBOL_GPL(nvdimm_attribute_group);
 397
 398 struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, void *provider_data,
 399                 const struct attribute_group **groups, unsigned long flags,
 400                 unsigned long cmd_mask, int num_flush,
 401                 struct resource *flush_wpq)
 402 {
 403         struct nvdimm *nvdimm = kzalloc(sizeof(*nvdimm), GFP_KERNEL);
 404         struct device *dev;
 405
 406         if (!nvdimm)
 407                 return NULL;
 408
 409         nvdimm->id = ida_simple_get(&dimm_ida, 0, 0, GFP_KERNEL);
 410         if (nvdimm->id < 0) {
 411                 kfree(nvdimm);
 412                 return NULL;
 413         }
 414         nvdimm->provider_data = provider_data;
 415         nvdimm->flags = flags;
 416         nvdimm->cmd_mask = cmd_mask;
 417         nvdimm->num_flush = num_flush;
 418         nvdimm->flush_wpq = flush_wpq;
 419         atomic_set(&nvdimm->busy, 0);
 420         dev = &nvdimm->dev;
 421         dev_set_name(dev, "nmem%d", nvdimm->id);
 422         dev->parent = &nvdimm_bus->dev;
 423         dev->type = &nvdimm_device_type;
 424         dev->devt = MKDEV(nvdimm_major, nvdimm->id);
 425         dev->groups = groups;
 426         nd_device_register(dev);
 427
 428         return nvdimm;
 429 }
 430 EXPORT_SYMBOL_GPL(nvdimm_create);
 431
 432 int alias_dpa_busy(struct device *dev, void *data)
 433 {
 434         resource_size_t map_end, blk_start, new;
 435         struct blk_alloc_info *info = data;
 436         struct nd_mapping *nd_mapping;
 437         struct nd_region *nd_region;
 438         struct nvdimm_drvdata *ndd;
 439         struct resource *res;
 440         int i;
 441
 442         if (!is_memory(dev))
 443                 return 0;
 444
 445         nd_region = to_nd_region(dev);
 446         for (i = 0; i < nd_region->ndr_mappings; i++) {
 447                 nd_mapping  = &nd_region->mapping[i];
 448                 if (nd_mapping->nvdimm == info->nd_mapping->nvdimm)
 449                         break;
 450         }
 451
 452         if (i >= nd_region->ndr_mappings)
 453                 return 0;
 454
 455         ndd = to_ndd(nd_mapping);
 456         map_end = nd_mapping->start + nd_mapping->size - 1;
 457         blk_start = nd_mapping->start;
 458
 459         /*
 460          * In the allocation case ->res is set to free space that we are
 461          * looking to validate against PMEM aliasing collision rules
 462          * (i.e. BLK is allocated after all aliased PMEM).
 463          */
 464         if (info->res) {
 465                 if (info->res->start >= nd_mapping->start
 466                                 && info->res->start < map_end)
 467                         /* pass */;
 468                 else
 469                         return 0;
 470         }
 471
 472  retry:
 473         /*
 474          * Find the free dpa from the end of the last pmem allocation to
 475          * the end of the interleave-set mapping.
 476          */
 477         for_each_dpa_resource(ndd, res) {
 478                 if (strncmp(res->name, "pmem", 4) != 0)
 479                         continue;
 480                 if ((res->start >= blk_start && res->start < map_end)
 481                                 || (res->end >= blk_start
 482                                         && res->end <= map_end)) {
 483                         new = max(blk_start, min(map_end + 1, res->end + 1));
 484                         if (new != blk_start) {
 485                                 blk_start = new;
 486                                 goto retry;
 487                         }
 488                 }
 489         }
 490
 491         /* update the free space range with the probed blk_start */
 492         if (info->res && blk_start > info->res->start) {
 493                 info->res->start = max(info->res->start, blk_start);
 494                 if (info->res->start > info->res->end)
 495                         info->res->end = info->res->start - 1;
 496                 return 1;
 497         }
 498
 499         info->available -= blk_start - nd_mapping->start;
 500
 501         return 0;
 502 }
 503
 504 /**
 505  * nd_blk_available_dpa - account the unused dpa of BLK region
 506  * @nd_mapping: container of dpa-resource-root + labels
 507  *
 508  * Unlike PMEM, BLK namespaces can occupy discontiguous DPA ranges, but
 509  * we arrange for them to never start at an lower dpa than the last
 510  * PMEM allocation in an aliased region.
 511  */
 512 resource_size_t nd_blk_available_dpa(struct nd_region *nd_region)
 513 {
 514         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
 515         struct nd_mapping *nd_mapping = &nd_region->mapping[0];
 516         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 517         struct blk_alloc_info info = {
 518                 .nd_mapping = nd_mapping,
 519                 .available = nd_mapping->size,
 520                 .res = NULL,
 521         };
 522         struct resource *res;
 523
 524         if (!ndd)
 525                 return 0;
 526
 527         device_for_each_child(&nvdimm_bus->dev, &info, alias_dpa_busy);
 528
 529         /* now account for busy blk allocations in unaliased dpa */
 530         for_each_dpa_resource(ndd, res) {
 531                 if (strncmp(res->name, "blk", 3) != 0)
 532                         continue;
 533                 info.available -= resource_size(res);
 534         }
 535
 536         return info.available;
 537 }
 538
 539 /**
 540  * nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
 541  * @nd_mapping: container of dpa-resource-root + labels
 542  * @nd_region: constrain available space check to this reference region
 543  * @overlap: calculate available space assuming this level of overlap
 544  *
 545  * Validate that a PMEM label, if present, aligns with the start of an
 546  * interleave set and truncate the available size at the lowest BLK
 547  * overlap point.
 548  *
 549  * The expectation is that this routine is called multiple times as it
 550  * probes for the largest BLK encroachment for any single member DIMM of
 551  * the interleave set.  Once that value is determined the PMEM-limit for
 552  * the set can be established.
 553  */
 554 resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
 555                 struct nd_mapping *nd_mapping, resource_size_t *overlap)
 556 {
 557         resource_size_t map_start, map_end, busy = 0, available, blk_start;
 558         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 559         struct resource *res;
 560         const char *reason;
 561
 562         if (!ndd)
 563                 return 0;
 564
 565         map_start = nd_mapping->start;
 566         map_end = map_start + nd_mapping->size - 1;
 567         blk_start = max(map_start, map_end + 1 - *overlap);
 568         for_each_dpa_resource(ndd, res) {
 569                 if (res->start >= map_start && res->start < map_end) {
 570                         if (strncmp(res->name, "blk", 3) == 0)
 571                                 blk_start = min(blk_start,
 572                                                 max(map_start, res->start));
 573                         else if (res->end > map_end) {
 574                                 reason = "misaligned to iset";
 575                                 goto err;
 576                         } else
 577                                 busy += resource_size(res);
 578                 } else if (res->end >= map_start && res->end <= map_end) {
 579                         if (strncmp(res->name, "blk", 3) == 0) {
 580                                 /*
 581                                  * If a BLK allocation overlaps the start of
 582                                  * PMEM the entire interleave set may now only
 583                                  * be used for BLK.
 584                                  */
 585                                 blk_start = map_start;
 586                         } else
 587                                 busy += resource_size(res);
 588                 } else if (map_start > res->start && map_start < res->end) {
 589                         /* total eclipse of the mapping */
 590                         busy += nd_mapping->size;
 591                         blk_start = map_start;
 592                 }
 593         }
 594
 595         *overlap = map_end + 1 - blk_start;
 596         available = blk_start - map_start;
 597         if (busy < available)
 598                 return available - busy;
 599         return 0;
 600
 601  err:
 602         nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
 603         return 0;
 604 }
 605
 606 void nvdimm_free_dpa(struct nvdimm_drvdata *ndd, struct resource *res)
 607 {
 608         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
 609         kfree(res->name);
 610         __release_region(&ndd->dpa, res->start, resource_size(res));
 611 }
 612
 613 struct resource *nvdimm_allocate_dpa(struct nvdimm_drvdata *ndd,
 614                 struct nd_label_id *label_id, resource_size_t start,
 615                 resource_size_t n)
 616 {
 617         char *name = kmemdup(label_id, sizeof(*label_id), GFP_KERNEL);
 618         struct resource *res;
 619
 620         if (!name)
 621                 return NULL;
 622
 623         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
 624         res = __request_region(&ndd->dpa, start, n, name, 0);
 625         if (!res)
 626                 kfree(name);
 627         return res;
 628 }
 629
 630 /**
 631  * nvdimm_allocated_dpa - sum up the dpa currently allocated to this label_id
 632  * @nvdimm: container of dpa-resource-root + labels
 633  * @label_id: dpa resource name of the form {pmem|blk}-<human readable uuid>
 634  */
 635 resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
 636                 struct nd_label_id *label_id)
 637 {
 638         resource_size_t allocated = 0;
 639         struct resource *res;
 640
 641         for_each_dpa_resource(ndd, res)
 642                 if (strcmp(res->name, label_id->id) == 0)
 643                         allocated += resource_size(res);
 644
 645         return allocated;
 646 }
 647
 648 static int count_dimms(struct device *dev, void *c)
 649 {
 650         int *count = c;
 651
 652         if (is_nvdimm(dev))
 653                 (*count)++;
 654         return 0;
 655 }
 656
 657 int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count)
 658 {
 659         int count = 0;
 660         /* Flush any possible dimm registration failures */
 661         nd_synchronize();
 662
 663         device_for_each_child(&nvdimm_bus->dev, &count, count_dimms);
 664         dev_dbg(&nvdimm_bus->dev, "count: %d\n", count);
 665         if (count != dimm_count)
 666                 return -ENXIO;
 667         return 0;
 668 }
 669 EXPORT_SYMBOL_GPL(nvdimm_bus_check_dimm_count);
 670
 671 void __exit nvdimm_devs_exit(void)
 672 {
 673         ida_destroy(&dimm_ida);
 674 }