drivers/nvdimm/region_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 #include <linux/scatterlist.h>
  14 #include <linux/highmem.h>
  15 #include <linux/sched.h>
  16 #include <linux/slab.h>
  17 #include <linux/hash.h>
  18 #include <linux/sort.h>
  19 #include <linux/io.h>
  20 #include <linux/nd.h>
  21 #include "nd-core.h"
  22 #include "nd.h"
  23
  24 /*
  25  * For readq() and writeq() on 32-bit builds, the hi-lo, lo-hi order is
  26  * irrelevant.
  27  */
  28 #include <linux/io-64-nonatomic-hi-lo.h>
  29
  30 static DEFINE_IDA(region_ida);
  31 static DEFINE_PER_CPU(int, flush_idx);
  32
  33 static int nvdimm_map_flush(struct device *dev, struct nvdimm *nvdimm, int dimm,
  34                 struct nd_region_data *ndrd)
  35 {
  36         int i, j;
  37
  38         dev_dbg(dev, "%s: map %d flush address%s\n", nvdimm_name(nvdimm),
  39                         nvdimm->num_flush, nvdimm->num_flush == 1 ? "" : "es");
  40         for (i = 0; i < (1 << ndrd->hints_shift); i++) {
  41                 struct resource *res = &nvdimm->flush_wpq[i];
  42                 unsigned long pfn = PHYS_PFN(res->start);
  43                 void __iomem *flush_page;
  44
  45                 /* check if flush hints share a page */
  46                 for (j = 0; j < i; j++) {
  47                         struct resource *res_j = &nvdimm->flush_wpq[j];
  48                         unsigned long pfn_j = PHYS_PFN(res_j->start);
  49
  50                         if (pfn == pfn_j)
  51                                 break;
  52                 }
  53
  54                 if (j < i)
  55                         flush_page = (void __iomem *) ((unsigned long)
  56                                         ndrd_get_flush_wpq(ndrd, dimm, j)
  57                                         & PAGE_MASK);
  58                 else
  59                         flush_page = devm_nvdimm_ioremap(dev,
  60                                         PFN_PHYS(pfn), PAGE_SIZE);
  61                 if (!flush_page)
  62                         return -ENXIO;
  63                 ndrd_set_flush_wpq(ndrd, dimm, i, flush_page
  64                                 + (res->start & ~PAGE_MASK));
  65         }
  66
  67         return 0;
  68 }
  69
  70 int nd_region_activate(struct nd_region *nd_region)
  71 {
  72         int i, j, num_flush = 0;
  73         struct nd_region_data *ndrd;
  74         struct device *dev = &nd_region->dev;
  75         size_t flush_data_size = sizeof(void *);
  76
  77         nvdimm_bus_lock(&nd_region->dev);
  78         for (i = 0; i < nd_region->ndr_mappings; i++) {
  79                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
  80                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
  81
  82                 if (test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags)) {
  83                         nvdimm_bus_unlock(&nd_region->dev);
  84                         return -EBUSY;
  85                 }
  86
  87                 /* at least one null hint slot per-dimm for the "no-hint" case */
  88                 flush_data_size += sizeof(void *);
  89                 num_flush = min_not_zero(num_flush, nvdimm->num_flush);
  90                 if (!nvdimm->num_flush)
  91                         continue;
  92                 flush_data_size += nvdimm->num_flush * sizeof(void *);
  93         }
  94         nvdimm_bus_unlock(&nd_region->dev);
  95
  96         ndrd = devm_kzalloc(dev, sizeof(*ndrd) + flush_data_size, GFP_KERNEL);
  97         if (!ndrd)
  98                 return -ENOMEM;
  99         dev_set_drvdata(dev, ndrd);
 100
 101         if (!num_flush)
 102                 return 0;
 103
 104         ndrd->hints_shift = ilog2(num_flush);
 105         for (i = 0; i < nd_region->ndr_mappings; i++) {
 106                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 107                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
 108                 int rc = nvdimm_map_flush(&nd_region->dev, nvdimm, i, ndrd);
 109
 110                 if (rc)
 111                         return rc;
 112         }
 113
 114         /*
 115          * Clear out entries that are duplicates. This should prevent the
 116          * extra flushings.
 117          */
 118         for (i = 0; i < nd_region->ndr_mappings - 1; i++) {
 119                 /* ignore if NULL already */
 120                 if (!ndrd_get_flush_wpq(ndrd, i, 0))
 121                         continue;
 122
 123                 for (j = i + 1; j < nd_region->ndr_mappings; j++)
 124                         if (ndrd_get_flush_wpq(ndrd, i, 0) ==
 125                             ndrd_get_flush_wpq(ndrd, j, 0))
 126                                 ndrd_set_flush_wpq(ndrd, j, 0, NULL);
 127         }
 128
 129         return 0;
 130 }
 131
 132 static void nd_region_release(struct device *dev)
 133 {
 134         struct nd_region *nd_region = to_nd_region(dev);
 135         u16 i;
 136
 137         for (i = 0; i < nd_region->ndr_mappings; i++) {
 138                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 139                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
 140
 141                 put_device(&nvdimm->dev);
 142         }
 143         free_percpu(nd_region->lane);
 144         ida_simple_remove(&region_ida, nd_region->id);
 145         if (is_nd_blk(dev))
 146                 kfree(to_nd_blk_region(dev));
 147         else
 148                 kfree(nd_region);
 149 }
 150
 151 static struct device_type nd_blk_device_type = {
 152         .name = "nd_blk",
 153         .release = nd_region_release,
 154 };
 155
 156 static struct device_type nd_pmem_device_type = {
 157         .name = "nd_pmem",
 158         .release = nd_region_release,
 159 };
 160
 161 static struct device_type nd_volatile_device_type = {
 162         .name = "nd_volatile",
 163         .release = nd_region_release,
 164 };
 165
 166 bool is_nd_pmem(struct device *dev)
 167 {
 168         return dev ? dev->type == &nd_pmem_device_type : false;
 169 }
 170
 171 bool is_nd_blk(struct device *dev)
 172 {
 173         return dev ? dev->type == &nd_blk_device_type : false;
 174 }
 175
 176 bool is_nd_volatile(struct device *dev)
 177 {
 178         return dev ? dev->type == &nd_volatile_device_type : false;
 179 }
 180
 181 struct nd_region *to_nd_region(struct device *dev)
 182 {
 183         struct nd_region *nd_region = container_of(dev, struct nd_region, dev);
 184
 185         WARN_ON(dev->type->release != nd_region_release);
 186         return nd_region;
 187 }
 188 EXPORT_SYMBOL_GPL(to_nd_region);
 189
 190 struct device *nd_region_dev(struct nd_region *nd_region)
 191 {
 192         if (!nd_region)
 193                 return NULL;
 194         return &nd_region->dev;
 195 }
 196 EXPORT_SYMBOL_GPL(nd_region_dev);
 197
 198 struct nd_blk_region *to_nd_blk_region(struct device *dev)
 199 {
 200         struct nd_region *nd_region = to_nd_region(dev);
 201
 202         WARN_ON(!is_nd_blk(dev));
 203         return container_of(nd_region, struct nd_blk_region, nd_region);
 204 }
 205 EXPORT_SYMBOL_GPL(to_nd_blk_region);
 206
 207 void *nd_region_provider_data(struct nd_region *nd_region)
 208 {
 209         return nd_region->provider_data;
 210 }
 211 EXPORT_SYMBOL_GPL(nd_region_provider_data);
 212
 213 void *nd_blk_region_provider_data(struct nd_blk_region *ndbr)
 214 {
 215         return ndbr->blk_provider_data;
 216 }
 217 EXPORT_SYMBOL_GPL(nd_blk_region_provider_data);
 218
 219 void nd_blk_region_set_provider_data(struct nd_blk_region *ndbr, void *data)
 220 {
 221         ndbr->blk_provider_data = data;
 222 }
 223 EXPORT_SYMBOL_GPL(nd_blk_region_set_provider_data);
 224
 225 /**
 226  * nd_region_to_nstype() - region to an integer namespace type
 227  * @nd_region: region-device to interrogate
 228  *
 229  * This is the 'nstype' attribute of a region as well, an input to the
 230  * MODALIAS for namespace devices, and bit number for a nvdimm_bus to match
 231  * namespace devices with namespace drivers.
 232  */
 233 int nd_region_to_nstype(struct nd_region *nd_region)
 234 {
 235         if (is_memory(&nd_region->dev)) {
 236                 u16 i, alias;
 237
 238                 for (i = 0, alias = 0; i < nd_region->ndr_mappings; i++) {
 239                         struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 240                         struct nvdimm *nvdimm = nd_mapping->nvdimm;
 241
 242                         if (test_bit(NDD_ALIASING, &nvdimm->flags))
 243                                 alias++;
 244                 }
 245                 if (alias)
 246                         return ND_DEVICE_NAMESPACE_PMEM;
 247                 else
 248                         return ND_DEVICE_NAMESPACE_IO;
 249         } else if (is_nd_blk(&nd_region->dev)) {
 250                 return ND_DEVICE_NAMESPACE_BLK;
 251         }
 252
 253         return 0;
 254 }
 255 EXPORT_SYMBOL(nd_region_to_nstype);
 256
 257 static ssize_t size_show(struct device *dev,
 258                 struct device_attribute *attr, char *buf)
 259 {
 260         struct nd_region *nd_region = to_nd_region(dev);
 261         unsigned long long size = 0;
 262
 263         if (is_memory(dev)) {
 264                 size = nd_region->ndr_size;
 265         } else if (nd_region->ndr_mappings == 1) {
 266                 struct nd_mapping *nd_mapping = &nd_region->mapping[0];
 267
 268                 size = nd_mapping->size;
 269         }
 270
 271         return sprintf(buf, "%llu\n", size);
 272 }
 273 static DEVICE_ATTR_RO(size);
 274
 275 static ssize_t deep_flush_show(struct device *dev,
 276                 struct device_attribute *attr, char *buf)
 277 {
 278         struct nd_region *nd_region = to_nd_region(dev);
 279
 280         /*
 281          * NOTE: in the nvdimm_has_flush() error case this attribute is
 282          * not visible.
 283          */
 284         return sprintf(buf, "%d\n", nvdimm_has_flush(nd_region));
 285 }
 286
 287 static ssize_t deep_flush_store(struct device *dev, struct device_attribute *attr,
 288                 const char *buf, size_t len)
 289 {
 290         bool flush;
 291         int rc = strtobool(buf, &flush);
 292         struct nd_region *nd_region = to_nd_region(dev);
 293
 294         if (rc)
 295                 return rc;
 296         if (!flush)
 297                 return -EINVAL;
 298         nvdimm_flush(nd_region);
 299
 300         return len;
 301 }
 302 static DEVICE_ATTR_RW(deep_flush);
 303
 304 static ssize_t mappings_show(struct device *dev,
 305                 struct device_attribute *attr, char *buf)
 306 {
 307         struct nd_region *nd_region = to_nd_region(dev);
 308
 309         return sprintf(buf, "%d\n", nd_region->ndr_mappings);
 310 }
 311 static DEVICE_ATTR_RO(mappings);
 312
 313 static ssize_t nstype_show(struct device *dev,
 314                 struct device_attribute *attr, char *buf)
 315 {
 316         struct nd_region *nd_region = to_nd_region(dev);
 317
 318         return sprintf(buf, "%d\n", nd_region_to_nstype(nd_region));
 319 }
 320 static DEVICE_ATTR_RO(nstype);
 321
 322 static ssize_t set_cookie_show(struct device *dev,
 323                 struct device_attribute *attr, char *buf)
 324 {
 325         struct nd_region *nd_region = to_nd_region(dev);
 326         struct nd_interleave_set *nd_set = nd_region->nd_set;
 327         ssize_t rc = 0;
 328
 329         if (is_memory(dev) && nd_set)
 330                 /* pass, should be precluded by region_visible */;
 331         else
 332                 return -ENXIO;
 333
 334         /*
 335          * The cookie to show depends on which specification of the
 336          * labels we are using. If there are not labels then default to
 337          * the v1.1 namespace label cookie definition. To read all this
 338          * data we need to wait for probing to settle.
 339          */
 340         device_lock(dev);
 341         nvdimm_bus_lock(dev);
 342         wait_nvdimm_bus_probe_idle(dev);
 343         if (nd_region->ndr_mappings) {
 344                 struct nd_mapping *nd_mapping = &nd_region->mapping[0];
 345                 struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 346
 347                 if (ndd) {
 348                         struct nd_namespace_index *nsindex;
 349
 350                         nsindex = to_namespace_index(ndd, ndd->ns_current);
 351                         rc = sprintf(buf, "%#llx\n",
 352                                         nd_region_interleave_set_cookie(nd_region,
 353                                                 nsindex));
 354                 }
 355         }
 356         nvdimm_bus_unlock(dev);
 357         device_unlock(dev);
 358
 359         if (rc)
 360                 return rc;
 361         return sprintf(buf, "%#llx\n", nd_set->cookie1);
 362 }
 363 static DEVICE_ATTR_RO(set_cookie);
 364
 365 resource_size_t nd_region_available_dpa(struct nd_region *nd_region)
 366 {
 367         resource_size_t blk_max_overlap = 0, available, overlap;
 368         int i;
 369
 370         WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
 371
 372  retry:
 373         available = 0;
 374         overlap = blk_max_overlap;
 375         for (i = 0; i < nd_region->ndr_mappings; i++) {
 376                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 377                 struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 378
 379                 /* if a dimm is disabled the available capacity is zero */
 380                 if (!ndd)
 381                         return 0;
 382
 383                 if (is_memory(&nd_region->dev)) {
 384                         available += nd_pmem_available_dpa(nd_region,
 385                                         nd_mapping, &overlap);
 386                         if (overlap > blk_max_overlap) {
 387                                 blk_max_overlap = overlap;
 388                                 goto retry;
 389                         }
 390                 } else if (is_nd_blk(&nd_region->dev))
 391                         available += nd_blk_available_dpa(nd_region);
 392         }
 393
 394         return available;
 395 }
 396
 397 resource_size_t nd_region_allocatable_dpa(struct nd_region *nd_region)
 398 {
 399         resource_size_t available = 0;
 400         int i;
 401
 402         if (is_memory(&nd_region->dev))
 403                 available = PHYS_ADDR_MAX;
 404
 405         WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
 406         for (i = 0; i < nd_region->ndr_mappings; i++) {
 407                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 408
 409                 if (is_memory(&nd_region->dev))
 410                         available = min(available,
 411                                         nd_pmem_max_contiguous_dpa(nd_region,
 412                                                                    nd_mapping));
 413                 else if (is_nd_blk(&nd_region->dev))
 414                         available += nd_blk_available_dpa(nd_region);
 415         }
 416         if (is_memory(&nd_region->dev))
 417                 return available * nd_region->ndr_mappings;
 418         return available;
 419 }
 420
 421 static ssize_t available_size_show(struct device *dev,
 422                 struct device_attribute *attr, char *buf)
 423 {
 424         struct nd_region *nd_region = to_nd_region(dev);
 425         unsigned long long available = 0;
 426
 427         /*
 428          * Flush in-flight updates and grab a snapshot of the available
 429          * size.  Of course, this value is potentially invalidated the
 430          * memory nvdimm_bus_lock() is dropped, but that's userspace's
 431          * problem to not race itself.
 432          */
 433         nvdimm_bus_lock(dev);
 434         wait_nvdimm_bus_probe_idle(dev);
 435         available = nd_region_available_dpa(nd_region);
 436         nvdimm_bus_unlock(dev);
 437
 438         return sprintf(buf, "%llu\n", available);
 439 }
 440 static DEVICE_ATTR_RO(available_size);
 441
 442 static ssize_t max_available_extent_show(struct device *dev,
 443                 struct device_attribute *attr, char *buf)
 444 {
 445         struct nd_region *nd_region = to_nd_region(dev);
 446         unsigned long long available = 0;
 447
 448         nvdimm_bus_lock(dev);
 449         wait_nvdimm_bus_probe_idle(dev);
 450         available = nd_region_allocatable_dpa(nd_region);
 451         nvdimm_bus_unlock(dev);
 452
 453         return sprintf(buf, "%llu\n", available);
 454 }
 455 static DEVICE_ATTR_RO(max_available_extent);
 456
 457 static ssize_t init_namespaces_show(struct device *dev,
 458                 struct device_attribute *attr, char *buf)
 459 {
 460         struct nd_region_data *ndrd = dev_get_drvdata(dev);
 461         ssize_t rc;
 462
 463         nvdimm_bus_lock(dev);
 464         if (ndrd)
 465                 rc = sprintf(buf, "%d/%d\n", ndrd->ns_active, ndrd->ns_count);
 466         else
 467                 rc = -ENXIO;
 468         nvdimm_bus_unlock(dev);
 469
 470         return rc;
 471 }
 472 static DEVICE_ATTR_RO(init_namespaces);
 473
 474 static ssize_t namespace_seed_show(struct device *dev,
 475                 struct device_attribute *attr, char *buf)
 476 {
 477         struct nd_region *nd_region = to_nd_region(dev);
 478         ssize_t rc;
 479
 480         nvdimm_bus_lock(dev);
 481         if (nd_region->ns_seed)
 482                 rc = sprintf(buf, "%s\n", dev_name(nd_region->ns_seed));
 483         else
 484                 rc = sprintf(buf, "\n");
 485         nvdimm_bus_unlock(dev);
 486         return rc;
 487 }
 488 static DEVICE_ATTR_RO(namespace_seed);
 489
 490 static ssize_t btt_seed_show(struct device *dev,
 491                 struct device_attribute *attr, char *buf)
 492 {
 493         struct nd_region *nd_region = to_nd_region(dev);
 494         ssize_t rc;
 495
 496         nvdimm_bus_lock(dev);
 497         if (nd_region->btt_seed)
 498                 rc = sprintf(buf, "%s\n", dev_name(nd_region->btt_seed));
 499         else
 500                 rc = sprintf(buf, "\n");
 501         nvdimm_bus_unlock(dev);
 502
 503         return rc;
 504 }
 505 static DEVICE_ATTR_RO(btt_seed);
 506
 507 static ssize_t pfn_seed_show(struct device *dev,
 508                 struct device_attribute *attr, char *buf)
 509 {
 510         struct nd_region *nd_region = to_nd_region(dev);
 511         ssize_t rc;
 512
 513         nvdimm_bus_lock(dev);
 514         if (nd_region->pfn_seed)
 515                 rc = sprintf(buf, "%s\n", dev_name(nd_region->pfn_seed));
 516         else
 517                 rc = sprintf(buf, "\n");
 518         nvdimm_bus_unlock(dev);
 519
 520         return rc;
 521 }
 522 static DEVICE_ATTR_RO(pfn_seed);
 523
 524 static ssize_t dax_seed_show(struct device *dev,
 525                 struct device_attribute *attr, char *buf)
 526 {
 527         struct nd_region *nd_region = to_nd_region(dev);
 528         ssize_t rc;
 529
 530         nvdimm_bus_lock(dev);
 531         if (nd_region->dax_seed)
 532                 rc = sprintf(buf, "%s\n", dev_name(nd_region->dax_seed));
 533         else
 534                 rc = sprintf(buf, "\n");
 535         nvdimm_bus_unlock(dev);
 536
 537         return rc;
 538 }
 539 static DEVICE_ATTR_RO(dax_seed);
 540
 541 static ssize_t read_only_show(struct device *dev,
 542                 struct device_attribute *attr, char *buf)
 543 {
 544         struct nd_region *nd_region = to_nd_region(dev);
 545
 546         return sprintf(buf, "%d\n", nd_region->ro);
 547 }
 548
 549 static ssize_t read_only_store(struct device *dev,
 550                 struct device_attribute *attr, const char *buf, size_t len)
 551 {
 552         bool ro;
 553         int rc = strtobool(buf, &ro);
 554         struct nd_region *nd_region = to_nd_region(dev);
 555
 556         if (rc)
 557                 return rc;
 558
 559         nd_region->ro = ro;
 560         return len;
 561 }
 562 static DEVICE_ATTR_RW(read_only);
 563
 564 static ssize_t region_badblocks_show(struct device *dev,
 565                 struct device_attribute *attr, char *buf)
 566 {
 567         struct nd_region *nd_region = to_nd_region(dev);
 568         ssize_t rc;
 569
 570         device_lock(dev);
 571         if (dev->driver)
 572                 rc = badblocks_show(&nd_region->bb, buf, 0);
 573         else
 574                 rc = -ENXIO;
 575         device_unlock(dev);
 576
 577         return rc;
 578 }
 579 static DEVICE_ATTR(badblocks, 0444, region_badblocks_show, NULL);
 580
 581 static ssize_t resource_show(struct device *dev,
 582                 struct device_attribute *attr, char *buf)
 583 {
 584         struct nd_region *nd_region = to_nd_region(dev);
 585
 586         return sprintf(buf, "%#llx\n", nd_region->ndr_start);
 587 }
 588 static DEVICE_ATTR_RO(resource);
 589
 590 static ssize_t persistence_domain_show(struct device *dev,
 591                 struct device_attribute *attr, char *buf)
 592 {
 593         struct nd_region *nd_region = to_nd_region(dev);
 594
 595         if (test_bit(ND_REGION_PERSIST_CACHE, &nd_region->flags))
 596                 return sprintf(buf, "cpu_cache\n");
 597         else if (test_bit(ND_REGION_PERSIST_MEMCTRL, &nd_region->flags))
 598                 return sprintf(buf, "memory_controller\n");
 599         else
 600                 return sprintf(buf, "\n");
 601 }
 602 static DEVICE_ATTR_RO(persistence_domain);
 603
 604 static struct attribute *nd_region_attributes[] = {
 605         &dev_attr_size.attr,
 606         &dev_attr_nstype.attr,
 607         &dev_attr_mappings.attr,
 608         &dev_attr_btt_seed.attr,
 609         &dev_attr_pfn_seed.attr,
 610         &dev_attr_dax_seed.attr,
 611         &dev_attr_deep_flush.attr,
 612         &dev_attr_read_only.attr,
 613         &dev_attr_set_cookie.attr,
 614         &dev_attr_available_size.attr,
 615         &dev_attr_max_available_extent.attr,
 616         &dev_attr_namespace_seed.attr,
 617         &dev_attr_init_namespaces.attr,
 618         &dev_attr_badblocks.attr,
 619         &dev_attr_resource.attr,
 620         &dev_attr_persistence_domain.attr,
 621         NULL,
 622 };
 623
 624 static umode_t region_visible(struct kobject *kobj, struct attribute *a, int n)
 625 {
 626         struct device *dev = container_of(kobj, typeof(*dev), kobj);
 627         struct nd_region *nd_region = to_nd_region(dev);
 628         struct nd_interleave_set *nd_set = nd_region->nd_set;
 629         int type = nd_region_to_nstype(nd_region);
 630
 631         if (!is_memory(dev) && a == &dev_attr_pfn_seed.attr)
 632                 return 0;
 633
 634         if (!is_memory(dev) && a == &dev_attr_dax_seed.attr)
 635                 return 0;
 636
 637         if (!is_nd_pmem(dev) && a == &dev_attr_badblocks.attr)
 638                 return 0;
 639
 640         if (a == &dev_attr_resource.attr) {
 641                 if (is_nd_pmem(dev))
 642                         return 0400;
 643                 else
 644                         return 0;
 645         }
 646
 647         if (a == &dev_attr_deep_flush.attr) {
 648                 int has_flush = nvdimm_has_flush(nd_region);
 649
 650                 if (has_flush == 1)
 651                         return a->mode;
 652                 else if (has_flush == 0)
 653                         return 0444;
 654                 else
 655                         return 0;
 656         }
 657
 658         if (a == &dev_attr_persistence_domain.attr) {
 659                 if ((nd_region->flags & (BIT(ND_REGION_PERSIST_CACHE)
 660                                         | BIT(ND_REGION_PERSIST_MEMCTRL))) == 0)
 661                         return 0;
 662                 return a->mode;
 663         }
 664
 665         if (a != &dev_attr_set_cookie.attr
 666                         && a != &dev_attr_available_size.attr)
 667                 return a->mode;
 668
 669         if ((type == ND_DEVICE_NAMESPACE_PMEM
 670                                 || type == ND_DEVICE_NAMESPACE_BLK)
 671                         && a == &dev_attr_available_size.attr)
 672                 return a->mode;
 673         else if (is_memory(dev) && nd_set)
 674                 return a->mode;
 675
 676         return 0;
 677 }
 678
 679 struct attribute_group nd_region_attribute_group = {
 680         .attrs = nd_region_attributes,
 681         .is_visible = region_visible,
 682 };
 683 EXPORT_SYMBOL_GPL(nd_region_attribute_group);
 684
 685 u64 nd_region_interleave_set_cookie(struct nd_region *nd_region,
 686                 struct nd_namespace_index *nsindex)
 687 {
 688         struct nd_interleave_set *nd_set = nd_region->nd_set;
 689
 690         if (!nd_set)
 691                 return 0;
 692
 693         if (nsindex && __le16_to_cpu(nsindex->major) == 1
 694                         && __le16_to_cpu(nsindex->minor) == 1)
 695                 return nd_set->cookie1;
 696         return nd_set->cookie2;
 697 }
 698
 699 u64 nd_region_interleave_set_altcookie(struct nd_region *nd_region)
 700 {
 701         struct nd_interleave_set *nd_set = nd_region->nd_set;
 702
 703         if (nd_set)
 704                 return nd_set->altcookie;
 705         return 0;
 706 }
 707
 708 void nd_mapping_free_labels(struct nd_mapping *nd_mapping)
 709 {
 710         struct nd_label_ent *label_ent, *e;
 711
 712         lockdep_assert_held(&nd_mapping->lock);
 713         list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
 714                 list_del(&label_ent->list);
 715                 kfree(label_ent);
 716         }
 717 }
 718
 719 /*
 720  * Upon successful probe/remove, take/release a reference on the
 721  * associated interleave set (if present), and plant new btt + namespace
 722  * seeds.  Also, on the removal of a BLK region, notify the provider to
 723  * disable the region.
 724  */
 725 static void nd_region_notify_driver_action(struct nvdimm_bus *nvdimm_bus,
 726                 struct device *dev, bool probe)
 727 {
 728         struct nd_region *nd_region;
 729
 730         if (!probe && is_nd_region(dev)) {
 731                 int i;
 732
 733                 nd_region = to_nd_region(dev);
 734                 for (i = 0; i < nd_region->ndr_mappings; i++) {
 735                         struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 736                         struct nvdimm_drvdata *ndd = nd_mapping->ndd;
 737                         struct nvdimm *nvdimm = nd_mapping->nvdimm;
 738
 739                         mutex_lock(&nd_mapping->lock);
 740                         nd_mapping_free_labels(nd_mapping);
 741                         mutex_unlock(&nd_mapping->lock);
 742
 743                         put_ndd(ndd);
 744                         nd_mapping->ndd = NULL;
 745                         if (ndd)
 746                                 atomic_dec(&nvdimm->busy);
 747                 }
 748         }
 749         if (dev->parent && is_nd_region(dev->parent) && probe) {
 750                 nd_region = to_nd_region(dev->parent);
 751                 nvdimm_bus_lock(dev);
 752                 if (nd_region->ns_seed == dev)
 753                         nd_region_create_ns_seed(nd_region);
 754                 nvdimm_bus_unlock(dev);
 755         }
 756         if (is_nd_btt(dev) && probe) {
 757                 struct nd_btt *nd_btt = to_nd_btt(dev);
 758
 759                 nd_region = to_nd_region(dev->parent);
 760                 nvdimm_bus_lock(dev);
 761                 if (nd_region->btt_seed == dev)
 762                         nd_region_create_btt_seed(nd_region);
 763                 if (nd_region->ns_seed == &nd_btt->ndns->dev)
 764                         nd_region_create_ns_seed(nd_region);
 765                 nvdimm_bus_unlock(dev);
 766         }
 767         if (is_nd_pfn(dev) && probe) {
 768                 struct nd_pfn *nd_pfn = to_nd_pfn(dev);
 769
 770                 nd_region = to_nd_region(dev->parent);
 771                 nvdimm_bus_lock(dev);
 772                 if (nd_region->pfn_seed == dev)
 773                         nd_region_create_pfn_seed(nd_region);
 774                 if (nd_region->ns_seed == &nd_pfn->ndns->dev)
 775                         nd_region_create_ns_seed(nd_region);
 776                 nvdimm_bus_unlock(dev);
 777         }
 778         if (is_nd_dax(dev) && probe) {
 779                 struct nd_dax *nd_dax = to_nd_dax(dev);
 780
 781                 nd_region = to_nd_region(dev->parent);
 782                 nvdimm_bus_lock(dev);
 783                 if (nd_region->dax_seed == dev)
 784                         nd_region_create_dax_seed(nd_region);
 785                 if (nd_region->ns_seed == &nd_dax->nd_pfn.ndns->dev)
 786                         nd_region_create_ns_seed(nd_region);
 787                 nvdimm_bus_unlock(dev);
 788         }
 789 }
 790
 791 void nd_region_probe_success(struct nvdimm_bus *nvdimm_bus, struct device *dev)
 792 {
 793         nd_region_notify_driver_action(nvdimm_bus, dev, true);
 794 }
 795
 796 void nd_region_disable(struct nvdimm_bus *nvdimm_bus, struct device *dev)
 797 {
 798         nd_region_notify_driver_action(nvdimm_bus, dev, false);
 799 }
 800
 801 static ssize_t mappingN(struct device *dev, char *buf, int n)
 802 {
 803         struct nd_region *nd_region = to_nd_region(dev);
 804         struct nd_mapping *nd_mapping;
 805         struct nvdimm *nvdimm;
 806
 807         if (n >= nd_region->ndr_mappings)
 808                 return -ENXIO;
 809         nd_mapping = &nd_region->mapping[n];
 810         nvdimm = nd_mapping->nvdimm;
 811
 812         return sprintf(buf, "%s,%llu,%llu,%d\n", dev_name(&nvdimm->dev),
 813                         nd_mapping->start, nd_mapping->size,
 814                         nd_mapping->position);
 815 }
 816
 817 #define REGION_MAPPING(idx) \
 818 static ssize_t mapping##idx##_show(struct device *dev,          \
 819                 struct device_attribute *attr, char *buf)       \
 820 {                                                               \
 821         return mappingN(dev, buf, idx);                         \
 822 }                                                               \
 823 static DEVICE_ATTR_RO(mapping##idx)
 824
 825 /*
 826  * 32 should be enough for a while, even in the presence of socket
 827  * interleave a 32-way interleave set is a degenerate case.
 828  */
 829 REGION_MAPPING(0);
 830 REGION_MAPPING(1);
 831 REGION_MAPPING(2);
 832 REGION_MAPPING(3);
 833 REGION_MAPPING(4);
 834 REGION_MAPPING(5);
 835 REGION_MAPPING(6);
 836 REGION_MAPPING(7);
 837 REGION_MAPPING(8);
 838 REGION_MAPPING(9);
 839 REGION_MAPPING(10);
 840 REGION_MAPPING(11);
 841 REGION_MAPPING(12);
 842 REGION_MAPPING(13);
 843 REGION_MAPPING(14);
 844 REGION_MAPPING(15);
 845 REGION_MAPPING(16);
 846 REGION_MAPPING(17);
 847 REGION_MAPPING(18);
 848 REGION_MAPPING(19);
 849 REGION_MAPPING(20);
 850 REGION_MAPPING(21);
 851 REGION_MAPPING(22);
 852 REGION_MAPPING(23);
 853 REGION_MAPPING(24);
 854 REGION_MAPPING(25);
 855 REGION_MAPPING(26);
 856 REGION_MAPPING(27);
 857 REGION_MAPPING(28);
 858 REGION_MAPPING(29);
 859 REGION_MAPPING(30);
 860 REGION_MAPPING(31);
 861
 862 static umode_t mapping_visible(struct kobject *kobj, struct attribute *a, int n)
 863 {
 864         struct device *dev = container_of(kobj, struct device, kobj);
 865         struct nd_region *nd_region = to_nd_region(dev);
 866
 867         if (n < nd_region->ndr_mappings)
 868                 return a->mode;
 869         return 0;
 870 }
 871
 872 static struct attribute *mapping_attributes[] = {
 873         &dev_attr_mapping0.attr,
 874         &dev_attr_mapping1.attr,
 875         &dev_attr_mapping2.attr,
 876         &dev_attr_mapping3.attr,
 877         &dev_attr_mapping4.attr,
 878         &dev_attr_mapping5.attr,
 879         &dev_attr_mapping6.attr,
 880         &dev_attr_mapping7.attr,
 881         &dev_attr_mapping8.attr,
 882         &dev_attr_mapping9.attr,
 883         &dev_attr_mapping10.attr,
 884         &dev_attr_mapping11.attr,
 885         &dev_attr_mapping12.attr,
 886         &dev_attr_mapping13.attr,
 887         &dev_attr_mapping14.attr,
 888         &dev_attr_mapping15.attr,
 889         &dev_attr_mapping16.attr,
 890         &dev_attr_mapping17.attr,
 891         &dev_attr_mapping18.attr,
 892         &dev_attr_mapping19.attr,
 893         &dev_attr_mapping20.attr,
 894         &dev_attr_mapping21.attr,
 895         &dev_attr_mapping22.attr,
 896         &dev_attr_mapping23.attr,
 897         &dev_attr_mapping24.attr,
 898         &dev_attr_mapping25.attr,
 899         &dev_attr_mapping26.attr,
 900         &dev_attr_mapping27.attr,
 901         &dev_attr_mapping28.attr,
 902         &dev_attr_mapping29.attr,
 903         &dev_attr_mapping30.attr,
 904         &dev_attr_mapping31.attr,
 905         NULL,
 906 };
 907
 908 struct attribute_group nd_mapping_attribute_group = {
 909         .is_visible = mapping_visible,
 910         .attrs = mapping_attributes,
 911 };
 912 EXPORT_SYMBOL_GPL(nd_mapping_attribute_group);
 913
 914 int nd_blk_region_init(struct nd_region *nd_region)
 915 {
 916         struct device *dev = &nd_region->dev;
 917         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 918
 919         if (!is_nd_blk(dev))
 920                 return 0;
 921
 922         if (nd_region->ndr_mappings < 1) {
 923                 dev_dbg(dev, "invalid BLK region\n");
 924                 return -ENXIO;
 925         }
 926
 927         return to_nd_blk_region(dev)->enable(nvdimm_bus, dev);
 928 }
 929
 930 /**
 931  * nd_region_acquire_lane - allocate and lock a lane
 932  * @nd_region: region id and number of lanes possible
 933  *
 934  * A lane correlates to a BLK-data-window and/or a log slot in the BTT.
 935  * We optimize for the common case where there are 256 lanes, one
 936  * per-cpu.  For larger systems we need to lock to share lanes.  For now
 937  * this implementation assumes the cost of maintaining an allocator for
 938  * free lanes is on the order of the lock hold time, so it implements a
 939  * static lane = cpu % num_lanes mapping.
 940  *
 941  * In the case of a BTT instance on top of a BLK namespace a lane may be
 942  * acquired recursively.  We lock on the first instance.
 943  *
 944  * In the case of a BTT instance on top of PMEM, we only acquire a lane
 945  * for the BTT metadata updates.
 946  */
 947 unsigned int nd_region_acquire_lane(struct nd_region *nd_region)
 948 {
 949         unsigned int cpu, lane;
 950
 951         cpu = get_cpu();
 952         if (nd_region->num_lanes < nr_cpu_ids) {
 953                 struct nd_percpu_lane *ndl_lock, *ndl_count;
 954
 955                 lane = cpu % nd_region->num_lanes;
 956                 ndl_count = per_cpu_ptr(nd_region->lane, cpu);
 957                 ndl_lock = per_cpu_ptr(nd_region->lane, lane);
 958                 if (ndl_count->count++ == 0)
 959                         spin_lock(&ndl_lock->lock);
 960         } else
 961                 lane = cpu;
 962
 963         return lane;
 964 }
 965 EXPORT_SYMBOL(nd_region_acquire_lane);
 966
 967 void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane)
 968 {
 969         if (nd_region->num_lanes < nr_cpu_ids) {
 970                 unsigned int cpu = get_cpu();
 971                 struct nd_percpu_lane *ndl_lock, *ndl_count;
 972
 973                 ndl_count = per_cpu_ptr(nd_region->lane, cpu);
 974                 ndl_lock = per_cpu_ptr(nd_region->lane, lane);
 975                 if (--ndl_count->count == 0)
 976                         spin_unlock(&ndl_lock->lock);
 977                 put_cpu();
 978         }
 979         put_cpu();
 980 }
 981 EXPORT_SYMBOL(nd_region_release_lane);
 982
 983 static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
 984                 struct nd_region_desc *ndr_desc, struct device_type *dev_type,
 985                 const char *caller)
 986 {
 987         struct nd_region *nd_region;
 988         struct device *dev;
 989         void *region_buf;
 990         unsigned int i;
 991         int ro = 0;
 992
 993         for (i = 0; i < ndr_desc->num_mappings; i++) {
 994                 struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
 995                 struct nvdimm *nvdimm = mapping->nvdimm;
 996
 997                 if ((mapping->start | mapping->size) % SZ_4K) {
 998                         dev_err(&nvdimm_bus->dev, "%s: %s mapping%d is not 4K aligned\n",
 999                                         caller, dev_name(&nvdimm->dev), i);
1000
1001                         return NULL;
1002                 }
1003
1004                 if (test_bit(NDD_UNARMED, &nvdimm->flags))
1005                         ro = 1;
1006         }
1007
1008         if (dev_type == &nd_blk_device_type) {
1009                 struct nd_blk_region_desc *ndbr_desc;
1010                 struct nd_blk_region *ndbr;
1011
1012                 ndbr_desc = to_blk_region_desc(ndr_desc);
1013                 ndbr = kzalloc(sizeof(*ndbr) + sizeof(struct nd_mapping)
1014                                 * ndr_desc->num_mappings,
1015                                 GFP_KERNEL);
1016                 if (ndbr) {
1017                         nd_region = &ndbr->nd_region;
1018                         ndbr->enable = ndbr_desc->enable;
1019                         ndbr->do_io = ndbr_desc->do_io;
1020                 }
1021                 region_buf = ndbr;
1022         } else {
1023                 nd_region = kzalloc(sizeof(struct nd_region)
1024                                 + sizeof(struct nd_mapping)
1025                                 * ndr_desc->num_mappings,
1026                                 GFP_KERNEL);
1027                 region_buf = nd_region;
1028         }
1029
1030         if (!region_buf)
1031                 return NULL;
1032         nd_region->id = ida_simple_get(&region_ida, 0, 0, GFP_KERNEL);
1033         if (nd_region->id < 0)
1034                 goto err_id;
1035
1036         nd_region->lane = alloc_percpu(struct nd_percpu_lane);
1037         if (!nd_region->lane)
1038                 goto err_percpu;
1039
1040         for (i = 0; i < nr_cpu_ids; i++) {
1041                 struct nd_percpu_lane *ndl;
1042
1043                 ndl = per_cpu_ptr(nd_region->lane, i);
1044                 spin_lock_init(&ndl->lock);
1045                 ndl->count = 0;
1046         }
1047
1048         for (i = 0; i < ndr_desc->num_mappings; i++) {
1049                 struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
1050                 struct nvdimm *nvdimm = mapping->nvdimm;
1051
1052                 nd_region->mapping[i].nvdimm = nvdimm;
1053                 nd_region->mapping[i].start = mapping->start;
1054                 nd_region->mapping[i].size = mapping->size;
1055                 nd_region->mapping[i].position = mapping->position;
1056                 INIT_LIST_HEAD(&nd_region->mapping[i].labels);
1057                 mutex_init(&nd_region->mapping[i].lock);
1058
1059                 get_device(&nvdimm->dev);
1060         }
1061         nd_region->ndr_mappings = ndr_desc->num_mappings;
1062         nd_region->provider_data = ndr_desc->provider_data;
1063         nd_region->nd_set = ndr_desc->nd_set;
1064         nd_region->num_lanes = ndr_desc->num_lanes;
1065         nd_region->flags = ndr_desc->flags;
1066         nd_region->ro = ro;
1067         nd_region->numa_node = ndr_desc->numa_node;
1068         ida_init(&nd_region->ns_ida);
1069         ida_init(&nd_region->btt_ida);
1070         ida_init(&nd_region->pfn_ida);
1071         ida_init(&nd_region->dax_ida);
1072         dev = &nd_region->dev;
1073         dev_set_name(dev, "region%d", nd_region->id);
1074         dev->parent = &nvdimm_bus->dev;
1075         dev->type = dev_type;
1076         dev->groups = ndr_desc->attr_groups;
1077         dev->of_node = ndr_desc->of_node;
1078         nd_region->ndr_size = resource_size(ndr_desc->res);
1079         nd_region->ndr_start = ndr_desc->res->start;
1080         nd_device_register(dev);
1081
1082         return nd_region;
1083
1084  err_percpu:
1085         ida_simple_remove(&region_ida, nd_region->id);
1086  err_id:
1087         kfree(region_buf);
1088         return NULL;
1089 }
1090
1091 struct nd_region *nvdimm_pmem_region_create(struct nvdimm_bus *nvdimm_bus,
1092                 struct nd_region_desc *ndr_desc)
1093 {
1094         ndr_desc->num_lanes = ND_MAX_LANES;
1095         return nd_region_create(nvdimm_bus, ndr_desc, &nd_pmem_device_type,
1096                         __func__);
1097 }
1098 EXPORT_SYMBOL_GPL(nvdimm_pmem_region_create);
1099
1100 struct nd_region *nvdimm_blk_region_create(struct nvdimm_bus *nvdimm_bus,
1101                 struct nd_region_desc *ndr_desc)
1102 {
1103         if (ndr_desc->num_mappings > 1)
1104                 return NULL;
1105         ndr_desc->num_lanes = min(ndr_desc->num_lanes, ND_MAX_LANES);
1106         return nd_region_create(nvdimm_bus, ndr_desc, &nd_blk_device_type,
1107                         __func__);
1108 }
1109 EXPORT_SYMBOL_GPL(nvdimm_blk_region_create);
1110
1111 struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus,
1112                 struct nd_region_desc *ndr_desc)
1113 {
1114         ndr_desc->num_lanes = ND_MAX_LANES;
1115         return nd_region_create(nvdimm_bus, ndr_desc, &nd_volatile_device_type,
1116                         __func__);
1117 }
1118 EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create);
1119
1120 /**
1121  * nvdimm_flush - flush any posted write queues between the cpu and pmem media
1122  * @nd_region: blk or interleaved pmem region
1123  */
1124 void nvdimm_flush(struct nd_region *nd_region)
1125 {
1126         struct nd_region_data *ndrd = dev_get_drvdata(&nd_region->dev);
1127         int i, idx;
1128
1129         /*
1130          * Try to encourage some diversity in flush hint addresses
1131          * across cpus assuming a limited number of flush hints.
1132          */
1133         idx = this_cpu_read(flush_idx);
1134         idx = this_cpu_add_return(flush_idx, hash_32(current->pid + idx, 8));
1135
1136         /*
1137          * The first wmb() is needed to 'sfence' all previous writes
1138          * such that they are architecturally visible for the platform
1139          * buffer flush.  Note that we've already arranged for pmem
1140          * writes to avoid the cache via memcpy_flushcache().  The final
1141          * wmb() ensures ordering for the NVDIMM flush write.
1142          */
1143         wmb();
1144         for (i = 0; i < nd_region->ndr_mappings; i++)
1145                 if (ndrd_get_flush_wpq(ndrd, i, 0))
1146                         writeq(1, ndrd_get_flush_wpq(ndrd, i, idx));
1147         wmb();
1148 }
1149 EXPORT_SYMBOL_GPL(nvdimm_flush);
1150
1151 /**
1152  * nvdimm_has_flush - determine write flushing requirements
1153  * @nd_region: blk or interleaved pmem region
1154  *
1155  * Returns 1 if writes require flushing
1156  * Returns 0 if writes do not require flushing
1157  * Returns -ENXIO if flushing capability can not be determined
1158  */
1159 int nvdimm_has_flush(struct nd_region *nd_region)
1160 {
1161         int i;
1162
1163         /* no nvdimm or pmem api == flushing capability unknown */
1164         if (nd_region->ndr_mappings == 0
1165                         || !IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API))
1166                 return -ENXIO;
1167
1168         for (i = 0; i < nd_region->ndr_mappings; i++) {
1169                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
1170                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
1171
1172                 /* flush hints present / available */
1173                 if (nvdimm->num_flush)
1174                         return 1;
1175         }
1176
1177         /*
1178          * The platform defines dimm devices without hints, assume
1179          * platform persistence mechanism like ADR
1180          */
1181         return 0;
1182 }
1183 EXPORT_SYMBOL_GPL(nvdimm_has_flush);
1184
1185 int nvdimm_has_cache(struct nd_region *nd_region)
1186 {
1187         return is_nd_pmem(&nd_region->dev) &&
1188                 !test_bit(ND_REGION_PERSIST_CACHE, &nd_region->flags);
1189 }
1190 EXPORT_SYMBOL_GPL(nvdimm_has_cache);
1191
1192 struct conflict_context {
1193         struct nd_region *nd_region;
1194         resource_size_t start, size;
1195 };
1196
1197 static int region_conflict(struct device *dev, void *data)
1198 {
1199         struct nd_region *nd_region;
1200         struct conflict_context *ctx = data;
1201         resource_size_t res_end, region_end, region_start;
1202
1203         if (!is_memory(dev))
1204                 return 0;
1205
1206         nd_region = to_nd_region(dev);
1207         if (nd_region == ctx->nd_region)
1208                 return 0;
1209
1210         res_end = ctx->start + ctx->size;
1211         region_start = nd_region->ndr_start;
1212         region_end = region_start + nd_region->ndr_size;
1213         if (ctx->start >= region_start && ctx->start < region_end)
1214                 return -EBUSY;
1215         if (res_end > region_start && res_end <= region_end)
1216                 return -EBUSY;
1217         return 0;
1218 }
1219
1220 int nd_region_conflict(struct nd_region *nd_region, resource_size_t start,
1221                 resource_size_t size)
1222 {
1223         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
1224         struct conflict_context ctx = {
1225                 .nd_region = nd_region,
1226                 .start = start,
1227                 .size = size,
1228         };
1229
1230         return device_for_each_child(&nvdimm_bus->dev, &ctx, region_conflict);
1231 }
1232
1233 void __exit nd_region_devs_exit(void)
1234 {
1235         ida_destroy(&region_ida);
1236 }