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_ALIASING, &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_aliasing(struct device *dev)
 177 {
 178         struct nvdimm *nvdimm = to_nvdimm(dev);
 179
 180         set_bit(NDD_ALIASING, &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 static struct device_type nvdimm_device_type = {
 206         .name = "nvdimm",
 207         .release = nvdimm_release,
 208 };
 209
 210 bool is_nvdimm(struct device *dev)
 211 {
 212         return dev->type == &nvdimm_device_type;
 213 }
 214
 215 struct nvdimm *to_nvdimm(struct device *dev)
 216 {
 217         struct nvdimm *nvdimm = container_of(dev, struct nvdimm, dev);
 218
 219         WARN_ON(!is_nvdimm(dev));
 220         return nvdimm;
 221 }
 222 EXPORT_SYMBOL_GPL(to_nvdimm);
 223
 224 struct nvdimm *nd_blk_region_to_dimm(struct nd_blk_region *ndbr)
 225 {
 226         struct nd_region *nd_region = &ndbr->nd_region;
 227         struct nd_mapping *nd_mapping = &nd_region->mapping[0];
 228
 229         return nd_mapping->nvdimm;
 230 }
 231 EXPORT_SYMBOL_GPL(nd_blk_region_to_dimm);
 232
 233 unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr)
 234 {
 235         /* pmem mapping properties are private to libnvdimm */
 236         return ARCH_MEMREMAP_PMEM;
 237 }
 238 EXPORT_SYMBOL_GPL(nd_blk_memremap_flags);
 239
 240 struct nvdimm_drvdata *to_ndd(struct nd_mapping *nd_mapping)
 241 {
 242         struct nvdimm *nvdimm = nd_mapping->nvdimm;
 243
 244         WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
 245
 246         return dev_get_drvdata(&nvdimm->dev);
 247 }
 248 EXPORT_SYMBOL(to_ndd);
 249
 250 void nvdimm_drvdata_release(struct kref *kref)
 251 {
 252         struct nvdimm_drvdata *ndd = container_of(kref, typeof(*ndd), kref);
 253         struct device *dev = ndd->dev;
 254         struct resource *res, *_r;
 255
 256         dev_dbg(dev, "trace\n");
 257         nvdimm_bus_lock(dev);
 258         for_each_dpa_resource_safe(ndd, res, _r)
 259                 nvdimm_free_dpa(ndd, res);
 260         nvdimm_bus_unlock(dev);
 261
 262         kvfree(ndd->data);
 263         kfree(ndd);
 264         put_device(dev);
 265 }
 266
 267 void get_ndd(struct nvdimm_drvdata *ndd)
 268 {
 269         kref_get(&ndd->kref);
 270 }
 271
 272 void put_ndd(struct nvdimm_drvdata *ndd)
 273 {
 274         if (ndd)
 275                 kref_put(&ndd->kref, nvdimm_drvdata_release);
 276 }
 277
 278 const char *nvdimm_name(struct nvdimm *nvdimm)
 279 {
 280         return dev_name(&nvdimm->dev);
 281 }
 282 EXPORT_SYMBOL_GPL(nvdimm_name);
 283
 284 struct kobject *nvdimm_kobj(struct nvdimm *nvdimm)
 285 {
 286         return &nvdimm->dev.kobj;
 287 }
 288 EXPORT_SYMBOL_GPL(nvdimm_kobj);
 289
 290 unsigned long nvdimm_cmd_mask(struct nvdimm *nvdimm)
 291 {
 292         return nvdimm->cmd_mask;
 293 }
 294 EXPORT_SYMBOL_GPL(nvdimm_cmd_mask);
 295
 296 void *nvdimm_provider_data(struct nvdimm *nvdimm)
 297 {
 298         if (nvdimm)
 299                 return nvdimm->provider_data;
 300         return NULL;
 301 }
 302 EXPORT_SYMBOL_GPL(nvdimm_provider_data);
 303
 304 static ssize_t commands_show(struct device *dev,
 305                 struct device_attribute *attr, char *buf)
 306 {
 307         struct nvdimm *nvdimm = to_nvdimm(dev);
 308         int cmd, len = 0;
 309
 310         if (!nvdimm->cmd_mask)
 311                 return sprintf(buf, "\n");
 312
 313         for_each_set_bit(cmd, &nvdimm->cmd_mask, BITS_PER_LONG)
 314                 len += sprintf(buf + len, "%s ", nvdimm_cmd_name(cmd));
 315         len += sprintf(buf + len, "\n");
 316         return len;
 317 }
 318 static DEVICE_ATTR_RO(commands);
 319
 320 static ssize_t flags_show(struct device *dev,
 321                 struct device_attribute *attr, char *buf)
 322 {
 323         struct nvdimm *nvdimm = to_nvdimm(dev);
 324
 325         return sprintf(buf, "%s%s\n",
 326                         test_bit(NDD_ALIASING, &nvdimm->flags) ? "alias " : "",
 327                         test_bit(NDD_LOCKED, &nvdimm->flags) ? "lock " : "");
 328 }
 329 static DEVICE_ATTR_RO(flags);
 330
 331 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 332                 char *buf)
 333 {
 334         struct nvdimm *nvdimm = to_nvdimm(dev);
 335
 336         /*
 337          * The state may be in the process of changing, userspace should
 338          * quiesce probing if it wants a static answer
 339          */
 340         nvdimm_bus_lock(dev);
 341         nvdimm_bus_unlock(dev);
 342         return sprintf(buf, "%s\n", atomic_read(&nvdimm->busy)
 343                         ? "active" : "idle");
 344 }
 345 static DEVICE_ATTR_RO(state);
 346
 347 static ssize_t __available_slots_show(struct nvdimm_drvdata *ndd, char *buf)
 348 {
 349         struct device *dev;
 350         ssize_t rc;
 351         u32 nfree;
 352
 353         if (!ndd)
 354                 return -ENXIO;
 355
 356         dev = ndd->dev;
 357         nvdimm_bus_lock(dev);
 358         nfree = nd_label_nfree(ndd);
 359         if (nfree - 1 > nfree) {
 360                 dev_WARN_ONCE(dev, 1, "we ate our last label?\n");
 361                 nfree = 0;
 362         } else
 363                 nfree--;
 364         rc = sprintf(buf, "%d\n", nfree);
 365         nvdimm_bus_unlock(dev);
 366         return rc;
 367 }
 368
 369 static ssize_t available_slots_show(struct device *dev,
 370                                     struct device_attribute *attr, char *buf)
 371 {
 372         ssize_t rc;
 373
 374         nd_device_lock(dev);
 375         rc = __available_slots_show(dev_get_drvdata(dev), buf);
 376         nd_device_unlock(dev);
 377
 378         return rc;
 379 }
 380 static DEVICE_ATTR_RO(available_slots);
 381
 382 __weak ssize_t security_show(struct device *dev,
 383                 struct device_attribute *attr, char *buf)
 384 {
 385         struct nvdimm *nvdimm = to_nvdimm(dev);
 386
 387         if (test_bit(NVDIMM_SECURITY_DISABLED, &nvdimm->sec.flags))
 388                 return sprintf(buf, "disabled\n");
 389         if (test_bit(NVDIMM_SECURITY_UNLOCKED, &nvdimm->sec.flags))
 390                 return sprintf(buf, "unlocked\n");
 391         if (test_bit(NVDIMM_SECURITY_LOCKED, &nvdimm->sec.flags))
 392                 return sprintf(buf, "locked\n");
 393         if (test_bit(NVDIMM_SECURITY_OVERWRITE, &nvdimm->sec.flags))
 394                 return sprintf(buf, "overwrite\n");
 395         return -ENOTTY;
 396 }
 397
 398 static ssize_t frozen_show(struct device *dev,
 399                 struct device_attribute *attr, char *buf)
 400 {
 401         struct nvdimm *nvdimm = to_nvdimm(dev);
 402
 403         return sprintf(buf, "%d\n", test_bit(NVDIMM_SECURITY_FROZEN,
 404                                 &nvdimm->sec.flags));
 405 }
 406 static DEVICE_ATTR_RO(frozen);
 407
 408 static ssize_t security_store(struct device *dev,
 409                 struct device_attribute *attr, const char *buf, size_t len)
 410
 411 {
 412         ssize_t rc;
 413
 414         /*
 415          * Require all userspace triggered security management to be
 416          * done while probing is idle and the DIMM is not in active use
 417          * in any region.
 418          */
 419         nd_device_lock(dev);
 420         nvdimm_bus_lock(dev);
 421         wait_nvdimm_bus_probe_idle(dev);
 422         rc = nvdimm_security_store(dev, buf, len);
 423         nvdimm_bus_unlock(dev);
 424         nd_device_unlock(dev);
 425
 426         return rc;
 427 }
 428 static DEVICE_ATTR_RW(security);
 429
 430 static struct attribute *nvdimm_attributes[] = {
 431         &dev_attr_state.attr,
 432         &dev_attr_flags.attr,
 433         &dev_attr_commands.attr,
 434         &dev_attr_available_slots.attr,
 435         &dev_attr_security.attr,
 436         &dev_attr_frozen.attr,
 437         NULL,
 438 };
 439
 440 static umode_t nvdimm_visible(struct kobject *kobj, struct attribute *a, int n)
 441 {
 442         struct device *dev = container_of(kobj, typeof(*dev), kobj);
 443         struct nvdimm *nvdimm = to_nvdimm(dev);
 444
 445         if (a != &dev_attr_security.attr && a != &dev_attr_frozen.attr)
 446                 return a->mode;
 447         if (!nvdimm->sec.flags)
 448                 return 0;
 449
 450         if (a == &dev_attr_security.attr) {
 451                 /* Are there any state mutation ops (make writable)? */
 452                 if (nvdimm->sec.ops->freeze || nvdimm->sec.ops->disable
 453                                 || nvdimm->sec.ops->change_key
 454                                 || nvdimm->sec.ops->erase
 455                                 || nvdimm->sec.ops->overwrite)
 456                         return a->mode;
 457                 return 0444;
 458         }
 459
 460         if (nvdimm->sec.ops->freeze)
 461                 return a->mode;
 462         return 0;
 463 }
 464
 465 struct attribute_group nvdimm_attribute_group = {
 466         .attrs = nvdimm_attributes,
 467         .is_visible = nvdimm_visible,
 468 };
 469 EXPORT_SYMBOL_GPL(nvdimm_attribute_group);
 470
 471 struct nvdimm *__nvdimm_create(struct nvdimm_bus *nvdimm_bus,
 472                 void *provider_data, const struct attribute_group **groups,
 473                 unsigned long flags, unsigned long cmd_mask, int num_flush,
 474                 struct resource *flush_wpq, const char *dimm_id,
 475                 const struct nvdimm_security_ops *sec_ops)
 476 {
 477         struct nvdimm *nvdimm = kzalloc(sizeof(*nvdimm), GFP_KERNEL);
 478         struct device *dev;
 479
 480         if (!nvdimm)
 481                 return NULL;
 482
 483         nvdimm->id = ida_simple_get(&dimm_ida, 0, 0, GFP_KERNEL);
 484         if (nvdimm->id < 0) {
 485                 kfree(nvdimm);
 486                 return NULL;
 487         }
 488
 489         nvdimm->dimm_id = dimm_id;
 490         nvdimm->provider_data = provider_data;
 491         if (noblk)
 492                 flags |= 1 << NDD_NOBLK;
 493         nvdimm->flags = flags;
 494         nvdimm->cmd_mask = cmd_mask;
 495         nvdimm->num_flush = num_flush;
 496         nvdimm->flush_wpq = flush_wpq;
 497         atomic_set(&nvdimm->busy, 0);
 498         dev = &nvdimm->dev;
 499         dev_set_name(dev, "nmem%d", nvdimm->id);
 500         dev->parent = &nvdimm_bus->dev;
 501         dev->type = &nvdimm_device_type;
 502         dev->devt = MKDEV(nvdimm_major, nvdimm->id);
 503         dev->groups = groups;
 504         nvdimm->sec.ops = sec_ops;
 505         nvdimm->sec.overwrite_tmo = 0;
 506         INIT_DELAYED_WORK(&nvdimm->dwork, nvdimm_security_overwrite_query);
 507         /*
 508          * Security state must be initialized before device_add() for
 509          * attribute visibility.
 510          */
 511         /* get security state and extended (master) state */
 512         nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
 513         nvdimm->sec.ext_flags = nvdimm_security_flags(nvdimm, NVDIMM_MASTER);
 514         nd_device_register(dev);
 515
 516         return nvdimm;
 517 }
 518 EXPORT_SYMBOL_GPL(__nvdimm_create);
 519
 520 static void shutdown_security_notify(void *data)
 521 {
 522         struct nvdimm *nvdimm = data;
 523
 524         sysfs_put(nvdimm->sec.overwrite_state);
 525 }
 526
 527 int nvdimm_security_setup_events(struct device *dev)
 528 {
 529         struct nvdimm *nvdimm = to_nvdimm(dev);
 530
 531         if (!nvdimm->sec.flags || !nvdimm->sec.ops
 532                         || !nvdimm->sec.ops->overwrite)
 533                 return 0;
 534         nvdimm->sec.overwrite_state = sysfs_get_dirent(dev->kobj.sd, "security");
 535         if (!nvdimm->sec.overwrite_state)
 536                 return -ENOMEM;
 537
 538         return devm_add_action_or_reset(dev, shutdown_security_notify, nvdimm);
 539 }
 540 EXPORT_SYMBOL_GPL(nvdimm_security_setup_events);
 541
 542 int nvdimm_in_overwrite(struct nvdimm *nvdimm)
 543 {
 544         return test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags);
 545 }
 546 EXPORT_SYMBOL_GPL(nvdimm_in_overwrite);
 547
 548 int nvdimm_security_freeze(struct nvdimm *nvdimm)
 549 {
 550         int rc;
 551
 552         WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
 553
 554         if (!nvdimm->sec.ops || !nvdimm->sec.ops->freeze)
 555                 return -EOPNOTSUPP;
 556
 557         if (!nvdimm->sec.flags)
 558                 return -EIO;
 559
 560         if (test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags)) {
 561                 dev_warn(&nvdimm->dev, "Overwrite operation in progress.\n");
 562                 return -EBUSY;
 563         }
 564
 565         rc = nvdimm->sec.ops->freeze(nvdimm);
 566         nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
 567
 568         return rc;
 569 }
 570
 571 int alias_dpa_busy(struct device *dev, void *data)
 572 {
 573         resource_size_t map_end, blk_start, new;
 574         struct blk_alloc_info *info = data;
 575         struct nd_mapping *nd_mapping;
 576         struct nd_region *nd_region;
 577         struct nvdimm_drvdata *ndd;
 578         struct resource *res;
 579         int i;
 580
 581         if (!is_memory(dev))
 582                 return 0;
 583
 584         nd_region = to_nd_region(dev);
 585         for (i = 0; i < nd_region->ndr_mappings; i++) {
 586                 nd_mapping  = &nd_region->mapping[i];
 587                 if (nd_mapping->nvdimm == info->nd_mapping->nvdimm)
 588                         break;
 589         }
 590
 591         if (i >= nd_region->ndr_mappings)
 592                 return 0;
 593
 594         ndd = to_ndd(nd_mapping);
 595         map_end = nd_mapping->start + nd_mapping->size - 1;
 596         blk_start = nd_mapping->start;
 597
 598         /*
 599          * In the allocation case ->res is set to free space that we are
 600          * looking to validate against PMEM aliasing collision rules
 601          * (i.e. BLK is allocated after all aliased PMEM).
 602          */
 603         if (info->res) {
 604                 if (info->res->start >= nd_mapping->start
 605                                 && info->res->start < map_end)
 606                         /* pass */;
 607                 else
 608                         return 0;
 609         }
 610
 611  retry:
 612         /*
 613          * Find the free dpa from the end of the last pmem allocation to
 614          * the end of the interleave-set mapping.
 615          */
 616         for_each_dpa_resource(ndd, res) {
 617                 if (strncmp(res->name, "pmem", 4) != 0)
 618                         continue;
 619                 if ((res->start >= blk_start && res->start < map_end)
 620                                 || (res->end >= blk_start
 621                                         && res->end <= map_end)) {
 622                         new = max(blk_start, min(map_end + 1, res->end + 1));
 623                         if (new != blk_start) {
 624                                 blk_start = new;
 625                                 goto retry;
 626                         }
 627                 }
 628         }
 629
 630         /* update the free space range with the probed blk_start */
 631         if (info->res && blk_start > info->res->start) {
 632                 info->res->start = max(info->res->start, blk_start);
 633                 if (info->res->start > info->res->end)
 634                         info->res->end = info->res->start - 1;
 635                 return 1;
 636         }
 637
 638         info->available -= blk_start - nd_mapping->start;
 639
 640         return 0;
 641 }
 642
 643 /**
 644  * nd_blk_available_dpa - account the unused dpa of BLK region
 645  * @nd_mapping: container of dpa-resource-root + labels
 646  *
 647  * Unlike PMEM, BLK namespaces can occupy discontiguous DPA ranges, but
 648  * we arrange for them to never start at an lower dpa than the last
 649  * PMEM allocation in an aliased region.
 650  */
 651 resource_size_t nd_blk_available_dpa(struct nd_region *nd_region)
 652 {
 653         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
 654         struct nd_mapping *nd_mapping = &nd_region->mapping[0];
 655         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 656         struct blk_alloc_info info = {
 657                 .nd_mapping = nd_mapping,
 658                 .available = nd_mapping->size,
 659                 .res = NULL,
 660         };
 661         struct resource *res;
 662
 663         if (!ndd)
 664                 return 0;
 665
 666         device_for_each_child(&nvdimm_bus->dev, &info, alias_dpa_busy);
 667
 668         /* now account for busy blk allocations in unaliased dpa */
 669         for_each_dpa_resource(ndd, res) {
 670                 if (strncmp(res->name, "blk", 3) != 0)
 671                         continue;
 672                 info.available -= resource_size(res);
 673         }
 674
 675         return info.available;
 676 }
 677
 678 /**
 679  * nd_pmem_max_contiguous_dpa - For the given dimm+region, return the max
 680  *                         contiguous unallocated dpa range.
 681  * @nd_region: constrain available space check to this reference region
 682  * @nd_mapping: container of dpa-resource-root + labels
 683  */
 684 resource_size_t nd_pmem_max_contiguous_dpa(struct nd_region *nd_region,
 685                                            struct nd_mapping *nd_mapping)
 686 {
 687         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 688         struct nvdimm_bus *nvdimm_bus;
 689         resource_size_t max = 0;
 690         struct resource *res;
 691
 692         /* if a dimm is disabled the available capacity is zero */
 693         if (!ndd)
 694                 return 0;
 695
 696         nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
 697         if (__reserve_free_pmem(&nd_region->dev, nd_mapping->nvdimm))
 698                 return 0;
 699         for_each_dpa_resource(ndd, res) {
 700                 if (strcmp(res->name, "pmem-reserve") != 0)
 701                         continue;
 702                 if (resource_size(res) > max)
 703                         max = resource_size(res);
 704         }
 705         release_free_pmem(nvdimm_bus, nd_mapping);
 706         return max;
 707 }
 708
 709 /**
 710  * nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
 711  * @nd_mapping: container of dpa-resource-root + labels
 712  * @nd_region: constrain available space check to this reference region
 713  * @overlap: calculate available space assuming this level of overlap
 714  *
 715  * Validate that a PMEM label, if present, aligns with the start of an
 716  * interleave set and truncate the available size at the lowest BLK
 717  * overlap point.
 718  *
 719  * The expectation is that this routine is called multiple times as it
 720  * probes for the largest BLK encroachment for any single member DIMM of
 721  * the interleave set.  Once that value is determined the PMEM-limit for
 722  * the set can be established.
 723  */
 724 resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
 725                 struct nd_mapping *nd_mapping, resource_size_t *overlap)
 726 {
 727         resource_size_t map_start, map_end, busy = 0, available, blk_start;
 728         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 729         struct resource *res;
 730         const char *reason;
 731
 732         if (!ndd)
 733                 return 0;
 734
 735         map_start = nd_mapping->start;
 736         map_end = map_start + nd_mapping->size - 1;
 737         blk_start = max(map_start, map_end + 1 - *overlap);
 738         for_each_dpa_resource(ndd, res) {
 739                 if (res->start >= map_start && res->start < map_end) {
 740                         if (strncmp(res->name, "blk", 3) == 0)
 741                                 blk_start = min(blk_start,
 742                                                 max(map_start, res->start));
 743                         else if (res->end > map_end) {
 744                                 reason = "misaligned to iset";
 745                                 goto err;
 746                         } else
 747                                 busy += resource_size(res);
 748                 } else if (res->end >= map_start && res->end <= map_end) {
 749                         if (strncmp(res->name, "blk", 3) == 0) {
 750                                 /*
 751                                  * If a BLK allocation overlaps the start of
 752                                  * PMEM the entire interleave set may now only
 753                                  * be used for BLK.
 754                                  */
 755                                 blk_start = map_start;
 756                         } else
 757                                 busy += resource_size(res);
 758                 } else if (map_start > res->start && map_start < res->end) {
 759                         /* total eclipse of the mapping */
 760                         busy += nd_mapping->size;
 761                         blk_start = map_start;
 762                 }
 763         }
 764
 765         *overlap = map_end + 1 - blk_start;
 766         available = blk_start - map_start;
 767         if (busy < available)
 768                 return available - busy;
 769         return 0;
 770
 771  err:
 772         nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
 773         return 0;
 774 }
 775
 776 void nvdimm_free_dpa(struct nvdimm_drvdata *ndd, struct resource *res)
 777 {
 778         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
 779         kfree(res->name);
 780         __release_region(&ndd->dpa, res->start, resource_size(res));
 781 }
 782
 783 struct resource *nvdimm_allocate_dpa(struct nvdimm_drvdata *ndd,
 784                 struct nd_label_id *label_id, resource_size_t start,
 785                 resource_size_t n)
 786 {
 787         char *name = kmemdup(label_id, sizeof(*label_id), GFP_KERNEL);
 788         struct resource *res;
 789
 790         if (!name)
 791                 return NULL;
 792
 793         WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
 794         res = __request_region(&ndd->dpa, start, n, name, 0);
 795         if (!res)
 796                 kfree(name);
 797         return res;
 798 }
 799
 800 /**
 801  * nvdimm_allocated_dpa - sum up the dpa currently allocated to this label_id
 802  * @nvdimm: container of dpa-resource-root + labels
 803  * @label_id: dpa resource name of the form {pmem|blk}-<human readable uuid>
 804  */
 805 resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
 806                 struct nd_label_id *label_id)
 807 {
 808         resource_size_t allocated = 0;
 809         struct resource *res;
 810
 811         for_each_dpa_resource(ndd, res)
 812                 if (strcmp(res->name, label_id->id) == 0)
 813                         allocated += resource_size(res);
 814
 815         return allocated;
 816 }
 817
 818 static int count_dimms(struct device *dev, void *c)
 819 {
 820         int *count = c;
 821
 822         if (is_nvdimm(dev))
 823                 (*count)++;
 824         return 0;
 825 }
 826
 827 int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count)
 828 {
 829         int count = 0;
 830         /* Flush any possible dimm registration failures */
 831         nd_synchronize();
 832
 833         device_for_each_child(&nvdimm_bus->dev, &count, count_dimms);
 834         dev_dbg(&nvdimm_bus->dev, "count: %d\n", count);
 835         if (count != dimm_count)
 836                 return -ENXIO;
 837         return 0;
 838 }
 839 EXPORT_SYMBOL_GPL(nvdimm_bus_check_dimm_count);
 840
 841 void __exit nvdimm_devs_exit(void)
 842 {
 843         ida_destroy(&dimm_ida);
 844 }