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 nvdimm_drvdata *ndd, char *buf)
 363 {
 364         struct device *dev;
 365         ssize_t rc;
 366         u32 nfree;
 367
 368         if (!ndd)
 369                 return -ENXIO;
 370
 371         dev = ndd->dev;
 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
 384 static ssize_t available_slots_show(struct device *dev,
 385                                     struct device_attribute *attr, char *buf)
 386 {
 387         ssize_t rc;
 388
 389         device_lock(dev);
 390         rc = __available_slots_show(dev_get_drvdata(dev), buf);
 391         device_unlock(dev);
 392
 393         return rc;
 394 }
 395 static DEVICE_ATTR_RO(available_slots);
 396
 397 static struct attribute *nvdimm_attributes[] = {
 398         &dev_attr_state.attr,
 399         &dev_attr_flags.attr,
 400         &dev_attr_commands.attr,
 401         &dev_attr_available_slots.attr,
 402         NULL,
 403 };
 404
 405 struct attribute_group nvdimm_attribute_group = {
 406         .attrs = nvdimm_attributes,
 407 };
 408 EXPORT_SYMBOL_GPL(nvdimm_attribute_group);
 409
 410 struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, void *provider_data,
 411                 const struct attribute_group **groups, unsigned long flags,
 412                 unsigned long cmd_mask, int num_flush,
 413                 struct resource *flush_wpq)
 414 {
 415         struct nvdimm *nvdimm = kzalloc(sizeof(*nvdimm), GFP_KERNEL);
 416         struct device *dev;
 417
 418         if (!nvdimm)
 419                 return NULL;
 420
 421         nvdimm->id = ida_simple_get(&dimm_ida, 0, 0, GFP_KERNEL);
 422         if (nvdimm->id < 0) {
 423                 kfree(nvdimm);
 424                 return NULL;
 425         }
 426         nvdimm->provider_data = provider_data;
 427         nvdimm->flags = flags;
 428         nvdimm->cmd_mask = cmd_mask;
 429         nvdimm->num_flush = num_flush;
 430         nvdimm->flush_wpq = flush_wpq;
 431         atomic_set(&nvdimm->busy, 0);
 432         dev = &nvdimm->dev;
 433         dev_set_name(dev, "nmem%d", nvdimm->id);
 434         dev->parent = &nvdimm_bus->dev;
 435         dev->type = &nvdimm_device_type;
 436         dev->devt = MKDEV(nvdimm_major, nvdimm->id);
 437         dev->groups = groups;
 438         nd_device_register(dev);
 439
 440         return nvdimm;
 441 }
 442 EXPORT_SYMBOL_GPL(nvdimm_create);
 443
 444 int alias_dpa_busy(struct device *dev, void *data)
 445 {
 446         resource_size_t map_end, blk_start, new;
 447         struct blk_alloc_info *info = data;
 448         struct nd_mapping *nd_mapping;
 449         struct nd_region *nd_region;
 450         struct nvdimm_drvdata *ndd;
 451         struct resource *res;
 452         int i;
 453
 454         if (!is_memory(dev))
 455                 return 0;
 456
 457         nd_region = to_nd_region(dev);
 458         for (i = 0; i < nd_region->ndr_mappings; i++) {
 459                 nd_mapping  = &nd_region->mapping[i];
 460                 if (nd_mapping->nvdimm == info->nd_mapping->nvdimm)
 461                         break;
 462         }
 463
 464         if (i >= nd_region->ndr_mappings)
 465                 return 0;
 466
 467         ndd = to_ndd(nd_mapping);
 468         map_end = nd_mapping->start + nd_mapping->size - 1;
 469         blk_start = nd_mapping->start;
 470
 471         /*
 472          * In the allocation case ->res is set to free space that we are
 473          * looking to validate against PMEM aliasing collision rules
 474          * (i.e. BLK is allocated after all aliased PMEM).
 475          */
 476         if (info->res) {
 477                 if (info->res->start >= nd_mapping->start
 478                                 && info->res->start < map_end)
 479                         /* pass */;
 480                 else
 481                         return 0;
 482         }
 483
 484  retry:
 485         /*
 486          * Find the free dpa from the end of the last pmem allocation to
 487          * the end of the interleave-set mapping.
 488          */
 489         for_each_dpa_resource(ndd, res) {
 490                 if (strncmp(res->name, "pmem", 4) != 0)
 491                         continue;
 492                 if ((res->start >= blk_start && res->start < map_end)
 493                                 || (res->end >= blk_start
 494                                         && res->end <= map_end)) {
 495                         new = max(blk_start, min(map_end + 1, res->end + 1));
 496                         if (new != blk_start) {
 497                                 blk_start = new;
 498                                 goto retry;
 499                         }
 500                 }
 501         }
 502
 503         /* update the free space range with the probed blk_start */
 504         if (info->res && blk_start > info->res->start) {
 505                 info->res->start = max(info->res->start, blk_start);
 506                 if (info->res->start > info->res->end)
 507                         info->res->end = info->res->start - 1;
 508                 return 1;
 509         }
 510
 511         info->available -= blk_start - nd_mapping->start;
 512
 513         return 0;
 514 }
 515
 516 /**
 517  * nd_blk_available_dpa - account the unused dpa of BLK region
 518  * @nd_mapping: container of dpa-resource-root + labels
 519  *
 520  * Unlike PMEM, BLK namespaces can occupy discontiguous DPA ranges, but
 521  * we arrange for them to never start at an lower dpa than the last
 522  * PMEM allocation in an aliased region.
 523  */
 524 resource_size_t nd_blk_available_dpa(struct nd_region *nd_region)
 525 {
 526         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
 527         struct nd_mapping *nd_mapping = &nd_region->mapping[0];
 528         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 529         struct blk_alloc_info info = {
 530                 .nd_mapping = nd_mapping,
 531                 .available = nd_mapping->size,
 532                 .res = NULL,
 533         };
 534         struct resource *res;
 535
 536         if (!ndd)
 537                 return 0;
 538
 539         device_for_each_child(&nvdimm_bus->dev, &info, alias_dpa_busy);
 540
 541         /* now account for busy blk allocations in unaliased dpa */
 542         for_each_dpa_resource(ndd, res) {
 543                 if (strncmp(res->name, "blk", 3) != 0)
 544                         continue;
 545                 info.available -= resource_size(res);
 546         }
 547
 548         return info.available;
 549 }
 550
 551 /**
 552  * nd_pmem_max_contiguous_dpa - For the given dimm+region, return the max
 553  *                         contiguous unallocated dpa range.
 554  * @nd_region: constrain available space check to this reference region
 555  * @nd_mapping: container of dpa-resource-root + labels
 556  */
 557 resource_size_t nd_pmem_max_contiguous_dpa(struct nd_region *nd_region,
 558                                            struct nd_mapping *nd_mapping)
 559 {
 560         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 561         struct nvdimm_bus *nvdimm_bus;
 562         resource_size_t max = 0;
 563         struct resource *res;
 564
 565         /* if a dimm is disabled the available capacity is zero */
 566         if (!ndd)
 567                 return 0;
 568
 569         nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
 570         if (__reserve_free_pmem(&nd_region->dev, nd_mapping->nvdimm))
 571                 return 0;
 572         for_each_dpa_resource(ndd, res) {
 573                 if (strcmp(res->name, "pmem-reserve") != 0)
 574                         continue;
 575                 if (resource_size(res) > max)
 576                         max = resource_size(res);
 577         }
 578         release_free_pmem(nvdimm_bus, nd_mapping);
 579         return max;
 580 }
 581
 582 /**
 583  * nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
 584  * @nd_mapping: container of dpa-resource-root + labels
 585  * @nd_region: constrain available space check to this reference region
 586  * @overlap: calculate available space assuming this level of overlap
 587  *
 588  * Validate that a PMEM label, if present, aligns with the start of an
 589  * interleave set and truncate the available size at the lowest BLK
 590  * overlap point.
 591  *
 592  * The expectation is that this routine is called multiple times as it
 593  * probes for the largest BLK encroachment for any single member DIMM of
 594  * the interleave set.  Once that value is determined the PMEM-limit for
 595  * the set can be established.
 596  */
 597 resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
 598                 struct nd_mapping *nd_mapping, resource_size_t *overlap)
 599 {
 600         resource_size_t map_start, map_end, busy = 0, available, blk_start;
 601         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 602         struct resource *res;
 603         const char *reason;
 604
 605         if (!ndd)
 606                 return 0;
 607
 608         map_start = nd_mapping->start;
 609         map_end = map_start + nd_mapping->size - 1;
 610         blk_start = max(map_start, map_end + 1 - *overlap);
 611         for_each_dpa_resource(ndd, res) {
 612                 if (res->start >= map_start && res->start < map_end) {
 613                         if (strncmp(res->name, "blk", 3) == 0)
 614                                 blk_start = min(blk_start,
 615                                                 max(map_start, res->start));
 616                         else if (res->end > map_end) {
 617                                 reason = "misaligned to iset";
 618                                 goto err;
 619                         } else
 620                                 busy += resource_size(res);
 621                 } else if (res->end >= map_start && res->end <= map_end) {
 622                         if (strncmp(res->name, "blk", 3) == 0) {
 623                                 /*
 624                                  * If a BLK allocation overlaps the start of
 625                                  * PMEM the entire interleave set may now only
 626                                  * be used for BLK.
 627                                  */
 628                                 blk_start = map_start;
 629                         } else
 630                                 busy += resource_size(res);
 631                 } else if (map_start > res->start && map_start < res->end) {
 632                         /* total eclipse of the mapping */
 633                         busy += nd_mapping->size;
 634                         blk_start = map_start;
 635                 }
 636         }
 637
 638         *overlap = map_end + 1 - blk_start;
 639         available = blk_start - map_start;
 640         if (busy < available)
 641                 return available - busy;
 642         return 0;
 643
 644  err:
 645         nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
 646         return 0;
 647 }
 648
 649 void nvdimm_free_dpa(struct nvdimm_drvdata *ndd, struct resource *res)
 650 {
 651         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
 652         kfree(res->name);
 653         __release_region(&ndd->dpa, res->start, resource_size(res));
 654 }
 655
 656 struct resource *nvdimm_allocate_dpa(struct nvdimm_drvdata *ndd,
 657                 struct nd_label_id *label_id, resource_size_t start,
 658                 resource_size_t n)
 659 {
 660         char *name = kmemdup(label_id, sizeof(*label_id), GFP_KERNEL);
 661         struct resource *res;
 662
 663         if (!name)
 664                 return NULL;
 665
 666         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
 667         res = __request_region(&ndd->dpa, start, n, name, 0);
 668         if (!res)
 669                 kfree(name);
 670         return res;
 671 }
 672
 673 /**
 674  * nvdimm_allocated_dpa - sum up the dpa currently allocated to this label_id
 675  * @nvdimm: container of dpa-resource-root + labels
 676  * @label_id: dpa resource name of the form {pmem|blk}-<human readable uuid>
 677  */
 678 resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
 679                 struct nd_label_id *label_id)
 680 {
 681         resource_size_t allocated = 0;
 682         struct resource *res;
 683
 684         for_each_dpa_resource(ndd, res)
 685                 if (strcmp(res->name, label_id->id) == 0)
 686                         allocated += resource_size(res);
 687
 688         return allocated;
 689 }
 690
 691 static int count_dimms(struct device *dev, void *c)
 692 {
 693         int *count = c;
 694
 695         if (is_nvdimm(dev))
 696                 (*count)++;
 697         return 0;
 698 }
 699
 700 int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count)
 701 {
 702         int count = 0;
 703         /* Flush any possible dimm registration failures */
 704         nd_synchronize();
 705
 706         device_for_each_child(&nvdimm_bus->dev, &count, count_dimms);
 707         dev_dbg(&nvdimm_bus->dev, "count: %d\n", count);
 708         if (count != dimm_count)
 709                 return -ENXIO;
 710         return 0;
 711 }
 712 EXPORT_SYMBOL_GPL(nvdimm_bus_check_dimm_count);
 713
 714 void __exit nvdimm_devs_exit(void)
 715 {
 716         ida_destroy(&dimm_ida);
 717 }