drivers/nvdimm/region_devs.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
   4  */
   5 #include <linux/scatterlist.h>
   6 #include <linux/memregion.h>
   7 #include <linux/highmem.h>
   8 #include <linux/sched.h>
   9 #include <linux/slab.h>
  10 #include <linux/hash.h>
  11 #include <linux/sort.h>
  12 #include <linux/io.h>
  13 #include <linux/nd.h>
  14 #include "nd-core.h"
  15 #include "nd.h"
  16
  17 /*
  18  * For readq() and writeq() on 32-bit builds, the hi-lo, lo-hi order is
  19  * irrelevant.
  20  */
  21 #include <linux/io-64-nonatomic-hi-lo.h>
  22
  23 static DEFINE_PER_CPU(int, flush_idx);
  24
  25 static int nvdimm_map_flush(struct device *dev, struct nvdimm *nvdimm, int dimm,
  26                 struct nd_region_data *ndrd)
  27 {
  28         int i, j;
  29
  30         dev_dbg(dev, "%s: map %d flush address%s\n", nvdimm_name(nvdimm),
  31                         nvdimm->num_flush, nvdimm->num_flush == 1 ? "" : "es");
  32         for (i = 0; i < (1 << ndrd->hints_shift); i++) {
  33                 struct resource *res = &nvdimm->flush_wpq[i];
  34                 unsigned long pfn = PHYS_PFN(res->start);
  35                 void __iomem *flush_page;
  36
  37                 /* check if flush hints share a page */
  38                 for (j = 0; j < i; j++) {
  39                         struct resource *res_j = &nvdimm->flush_wpq[j];
  40                         unsigned long pfn_j = PHYS_PFN(res_j->start);
  41
  42                         if (pfn == pfn_j)
  43                                 break;
  44                 }
  45
  46                 if (j < i)
  47                         flush_page = (void __iomem *) ((unsigned long)
  48                                         ndrd_get_flush_wpq(ndrd, dimm, j)
  49                                         & PAGE_MASK);
  50                 else
  51                         flush_page = devm_nvdimm_ioremap(dev,
  52                                         PFN_PHYS(pfn), PAGE_SIZE);
  53                 if (!flush_page)
  54                         return -ENXIO;
  55                 ndrd_set_flush_wpq(ndrd, dimm, i, flush_page
  56                                 + (res->start & ~PAGE_MASK));
  57         }
  58
  59         return 0;
  60 }
  61
  62 int nd_region_activate(struct nd_region *nd_region)
  63 {
  64         int i, j, num_flush = 0;
  65         struct nd_region_data *ndrd;
  66         struct device *dev = &nd_region->dev;
  67         size_t flush_data_size = sizeof(void *);
  68
  69         nvdimm_bus_lock(&nd_region->dev);
  70         for (i = 0; i < nd_region->ndr_mappings; i++) {
  71                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
  72                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
  73
  74                 if (test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags)) {
  75                         nvdimm_bus_unlock(&nd_region->dev);
  76                         return -EBUSY;
  77                 }
  78
  79                 /* at least one null hint slot per-dimm for the "no-hint" case */
  80                 flush_data_size += sizeof(void *);
  81                 num_flush = min_not_zero(num_flush, nvdimm->num_flush);
  82                 if (!nvdimm->num_flush)
  83                         continue;
  84                 flush_data_size += nvdimm->num_flush * sizeof(void *);
  85         }
  86         nvdimm_bus_unlock(&nd_region->dev);
  87
  88         ndrd = devm_kzalloc(dev, sizeof(*ndrd) + flush_data_size, GFP_KERNEL);
  89         if (!ndrd)
  90                 return -ENOMEM;
  91         dev_set_drvdata(dev, ndrd);
  92
  93         if (!num_flush)
  94                 return 0;
  95
  96         ndrd->hints_shift = ilog2(num_flush);
  97         for (i = 0; i < nd_region->ndr_mappings; i++) {
  98                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
  99                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
 100                 int rc = nvdimm_map_flush(&nd_region->dev, nvdimm, i, ndrd);
 101
 102                 if (rc)
 103                         return rc;
 104         }
 105
 106         /*
 107          * Clear out entries that are duplicates. This should prevent the
 108          * extra flushings.
 109          */
 110         for (i = 0; i < nd_region->ndr_mappings - 1; i++) {
 111                 /* ignore if NULL already */
 112                 if (!ndrd_get_flush_wpq(ndrd, i, 0))
 113                         continue;
 114
 115                 for (j = i + 1; j < nd_region->ndr_mappings; j++)
 116                         if (ndrd_get_flush_wpq(ndrd, i, 0) ==
 117                             ndrd_get_flush_wpq(ndrd, j, 0))
 118                                 ndrd_set_flush_wpq(ndrd, j, 0, NULL);
 119         }
 120
 121         return 0;
 122 }
 123
 124 static void nd_region_release(struct device *dev)
 125 {
 126         struct nd_region *nd_region = to_nd_region(dev);
 127         u16 i;
 128
 129         for (i = 0; i < nd_region->ndr_mappings; i++) {
 130                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 131                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
 132
 133                 put_device(&nvdimm->dev);
 134         }
 135         free_percpu(nd_region->lane);
 136         if (!test_bit(ND_REGION_CXL, &nd_region->flags))
 137                 memregion_free(nd_region->id);
 138         kfree(nd_region);
 139 }
 140
 141 struct nd_region *to_nd_region(struct device *dev)
 142 {
 143         struct nd_region *nd_region = container_of(dev, struct nd_region, dev);
 144
 145         WARN_ON(dev->type->release != nd_region_release);
 146         return nd_region;
 147 }
 148 EXPORT_SYMBOL_GPL(to_nd_region);
 149
 150 struct device *nd_region_dev(struct nd_region *nd_region)
 151 {
 152         if (!nd_region)
 153                 return NULL;
 154         return &nd_region->dev;
 155 }
 156 EXPORT_SYMBOL_GPL(nd_region_dev);
 157
 158 void *nd_region_provider_data(struct nd_region *nd_region)
 159 {
 160         return nd_region->provider_data;
 161 }
 162 EXPORT_SYMBOL_GPL(nd_region_provider_data);
 163
 164 /**
 165  * nd_region_to_nstype() - region to an integer namespace type
 166  * @nd_region: region-device to interrogate
 167  *
 168  * This is the 'nstype' attribute of a region as well, an input to the
 169  * MODALIAS for namespace devices, and bit number for a nvdimm_bus to match
 170  * namespace devices with namespace drivers.
 171  */
 172 int nd_region_to_nstype(struct nd_region *nd_region)
 173 {
 174         if (is_memory(&nd_region->dev)) {
 175                 u16 i, label;
 176
 177                 for (i = 0, label = 0; i < nd_region->ndr_mappings; i++) {
 178                         struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 179                         struct nvdimm *nvdimm = nd_mapping->nvdimm;
 180
 181                         if (test_bit(NDD_LABELING, &nvdimm->flags))
 182                                 label++;
 183                 }
 184                 if (label)
 185                         return ND_DEVICE_NAMESPACE_PMEM;
 186                 else
 187                         return ND_DEVICE_NAMESPACE_IO;
 188         }
 189
 190         return 0;
 191 }
 192 EXPORT_SYMBOL(nd_region_to_nstype);
 193
 194 static unsigned long long region_size(struct nd_region *nd_region)
 195 {
 196         if (is_memory(&nd_region->dev)) {
 197                 return nd_region->ndr_size;
 198         } else if (nd_region->ndr_mappings == 1) {
 199                 struct nd_mapping *nd_mapping = &nd_region->mapping[0];
 200
 201                 return nd_mapping->size;
 202         }
 203
 204         return 0;
 205 }
 206
 207 static ssize_t size_show(struct device *dev,
 208                 struct device_attribute *attr, char *buf)
 209 {
 210         struct nd_region *nd_region = to_nd_region(dev);
 211
 212         return sprintf(buf, "%llu\n", region_size(nd_region));
 213 }
 214 static DEVICE_ATTR_RO(size);
 215
 216 static ssize_t deep_flush_show(struct device *dev,
 217                 struct device_attribute *attr, char *buf)
 218 {
 219         struct nd_region *nd_region = to_nd_region(dev);
 220
 221         /*
 222          * NOTE: in the nvdimm_has_flush() error case this attribute is
 223          * not visible.
 224          */
 225         return sprintf(buf, "%d\n", nvdimm_has_flush(nd_region));
 226 }
 227
 228 static ssize_t deep_flush_store(struct device *dev, struct device_attribute *attr,
 229                 const char *buf, size_t len)
 230 {
 231         bool flush;
 232         int rc = strtobool(buf, &flush);
 233         struct nd_region *nd_region = to_nd_region(dev);
 234
 235         if (rc)
 236                 return rc;
 237         if (!flush)
 238                 return -EINVAL;
 239         rc = nvdimm_flush(nd_region, NULL);
 240         if (rc)
 241                 return rc;
 242
 243         return len;
 244 }
 245 static DEVICE_ATTR_RW(deep_flush);
 246
 247 static ssize_t mappings_show(struct device *dev,
 248                 struct device_attribute *attr, char *buf)
 249 {
 250         struct nd_region *nd_region = to_nd_region(dev);
 251
 252         return sprintf(buf, "%d\n", nd_region->ndr_mappings);
 253 }
 254 static DEVICE_ATTR_RO(mappings);
 255
 256 static ssize_t nstype_show(struct device *dev,
 257                 struct device_attribute *attr, char *buf)
 258 {
 259         struct nd_region *nd_region = to_nd_region(dev);
 260
 261         return sprintf(buf, "%d\n", nd_region_to_nstype(nd_region));
 262 }
 263 static DEVICE_ATTR_RO(nstype);
 264
 265 static ssize_t set_cookie_show(struct device *dev,
 266                 struct device_attribute *attr, char *buf)
 267 {
 268         struct nd_region *nd_region = to_nd_region(dev);
 269         struct nd_interleave_set *nd_set = nd_region->nd_set;
 270         ssize_t rc = 0;
 271
 272         if (is_memory(dev) && nd_set)
 273                 /* pass, should be precluded by region_visible */;
 274         else
 275                 return -ENXIO;
 276
 277         /*
 278          * The cookie to show depends on which specification of the
 279          * labels we are using. If there are not labels then default to
 280          * the v1.1 namespace label cookie definition. To read all this
 281          * data we need to wait for probing to settle.
 282          */
 283         device_lock(dev);
 284         nvdimm_bus_lock(dev);
 285         wait_nvdimm_bus_probe_idle(dev);
 286         if (nd_region->ndr_mappings) {
 287                 struct nd_mapping *nd_mapping = &nd_region->mapping[0];
 288                 struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 289
 290                 if (ndd) {
 291                         struct nd_namespace_index *nsindex;
 292
 293                         nsindex = to_namespace_index(ndd, ndd->ns_current);
 294                         rc = sprintf(buf, "%#llx\n",
 295                                         nd_region_interleave_set_cookie(nd_region,
 296                                                 nsindex));
 297                 }
 298         }
 299         nvdimm_bus_unlock(dev);
 300         device_unlock(dev);
 301
 302         if (rc)
 303                 return rc;
 304         return sprintf(buf, "%#llx\n", nd_set->cookie1);
 305 }
 306 static DEVICE_ATTR_RO(set_cookie);
 307
 308 resource_size_t nd_region_available_dpa(struct nd_region *nd_region)
 309 {
 310         resource_size_t available;
 311         int i;
 312
 313         WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
 314
 315         available = 0;
 316         for (i = 0; i < nd_region->ndr_mappings; i++) {
 317                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 318                 struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 319
 320                 /* if a dimm is disabled the available capacity is zero */
 321                 if (!ndd)
 322                         return 0;
 323
 324                 available += nd_pmem_available_dpa(nd_region, nd_mapping);
 325         }
 326
 327         return available;
 328 }
 329
 330 resource_size_t nd_region_allocatable_dpa(struct nd_region *nd_region)
 331 {
 332         resource_size_t avail = 0;
 333         int i;
 334
 335         WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
 336         for (i = 0; i < nd_region->ndr_mappings; i++) {
 337                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
 338
 339                 avail = min_not_zero(avail, nd_pmem_max_contiguous_dpa(
 340                                                     nd_region, nd_mapping));
 341         }
 342         return avail * nd_region->ndr_mappings;
 343 }
 344
 345 static ssize_t available_size_show(struct device *dev,
 346                 struct device_attribute *attr, char *buf)
 347 {
 348         struct nd_region *nd_region = to_nd_region(dev);
 349         unsigned long long available = 0;
 350
 351         /*
 352          * Flush in-flight updates and grab a snapshot of the available
 353          * size.  Of course, this value is potentially invalidated the
 354          * memory nvdimm_bus_lock() is dropped, but that's userspace's
 355          * problem to not race itself.
 356          */
 357         device_lock(dev);
 358         nvdimm_bus_lock(dev);
 359         wait_nvdimm_bus_probe_idle(dev);
 360         available = nd_region_available_dpa(nd_region);
 361         nvdimm_bus_unlock(dev);
 362         device_unlock(dev);
 363
 364         return sprintf(buf, "%llu\n", available);
 365 }
 366 static DEVICE_ATTR_RO(available_size);
 367
 368 static ssize_t max_available_extent_show(struct device *dev,
 369                 struct device_attribute *attr, char *buf)
 370 {
 371         struct nd_region *nd_region = to_nd_region(dev);
 372         unsigned long long available = 0;
 373
 374         device_lock(dev);
 375         nvdimm_bus_lock(dev);
 376         wait_nvdimm_bus_probe_idle(dev);
 377         available = nd_region_allocatable_dpa(nd_region);
 378         nvdimm_bus_unlock(dev);
 379         device_unlock(dev);
 380
 381         return sprintf(buf, "%llu\n", available);
 382 }
 383 static DEVICE_ATTR_RO(max_available_extent);
 384
 385 static ssize_t init_namespaces_show(struct device *dev,
 386                 struct device_attribute *attr, char *buf)
 387 {
 388         struct nd_region_data *ndrd = dev_get_drvdata(dev);
 389         ssize_t rc;
 390
 391         nvdimm_bus_lock(dev);
 392         if (ndrd)
 393                 rc = sprintf(buf, "%d/%d\n", ndrd->ns_active, ndrd->ns_count);
 394         else
 395                 rc = -ENXIO;
 396         nvdimm_bus_unlock(dev);
 397
 398         return rc;
 399 }
 400 static DEVICE_ATTR_RO(init_namespaces);
 401
 402 static ssize_t namespace_seed_show(struct device *dev,
 403                 struct device_attribute *attr, char *buf)
 404 {
 405         struct nd_region *nd_region = to_nd_region(dev);
 406         ssize_t rc;
 407
 408         nvdimm_bus_lock(dev);
 409         if (nd_region->ns_seed)
 410                 rc = sprintf(buf, "%s\n", dev_name(nd_region->ns_seed));
 411         else
 412                 rc = sprintf(buf, "\n");
 413         nvdimm_bus_unlock(dev);
 414         return rc;
 415 }
 416 static DEVICE_ATTR_RO(namespace_seed);
 417
 418 static ssize_t btt_seed_show(struct device *dev,
 419                 struct device_attribute *attr, char *buf)
 420 {
 421         struct nd_region *nd_region = to_nd_region(dev);
 422         ssize_t rc;
 423
 424         nvdimm_bus_lock(dev);
 425         if (nd_region->btt_seed)
 426                 rc = sprintf(buf, "%s\n", dev_name(nd_region->btt_seed));
 427         else
 428                 rc = sprintf(buf, "\n");
 429         nvdimm_bus_unlock(dev);
 430
 431         return rc;
 432 }
 433 static DEVICE_ATTR_RO(btt_seed);
 434
 435 static ssize_t pfn_seed_show(struct device *dev,
 436                 struct device_attribute *attr, char *buf)
 437 {
 438         struct nd_region *nd_region = to_nd_region(dev);
 439         ssize_t rc;
 440
 441         nvdimm_bus_lock(dev);
 442         if (nd_region->pfn_seed)
 443                 rc = sprintf(buf, "%s\n", dev_name(nd_region->pfn_seed));
 444         else
 445                 rc = sprintf(buf, "\n");
 446         nvdimm_bus_unlock(dev);
 447
 448         return rc;
 449 }
 450 static DEVICE_ATTR_RO(pfn_seed);
 451
 452 static ssize_t dax_seed_show(struct device *dev,
 453                 struct device_attribute *attr, char *buf)
 454 {
 455         struct nd_region *nd_region = to_nd_region(dev);
 456         ssize_t rc;
 457
 458         nvdimm_bus_lock(dev);
 459         if (nd_region->dax_seed)
 460                 rc = sprintf(buf, "%s\n", dev_name(nd_region->dax_seed));
 461         else
 462                 rc = sprintf(buf, "\n");
 463         nvdimm_bus_unlock(dev);
 464
 465         return rc;
 466 }
 467 static DEVICE_ATTR_RO(dax_seed);
 468
 469 static ssize_t read_only_show(struct device *dev,
 470                 struct device_attribute *attr, char *buf)
 471 {
 472         struct nd_region *nd_region = to_nd_region(dev);
 473
 474         return sprintf(buf, "%d\n", nd_region->ro);
 475 }
 476
 477 static int revalidate_read_only(struct device *dev, void *data)
 478 {
 479         nd_device_notify(dev, NVDIMM_REVALIDATE_REGION);
 480         return 0;
 481 }
 482
 483 static ssize_t read_only_store(struct device *dev,
 484                 struct device_attribute *attr, const char *buf, size_t len)
 485 {
 486         bool ro;
 487         int rc = strtobool(buf, &ro);
 488         struct nd_region *nd_region = to_nd_region(dev);
 489
 490         if (rc)
 491                 return rc;
 492
 493         nd_region->ro = ro;
 494         device_for_each_child(dev, NULL, revalidate_read_only);
 495         return len;
 496 }
 497 static DEVICE_ATTR_RW(read_only);
 498
 499 static ssize_t align_show(struct device *dev,
 500                 struct device_attribute *attr, char *buf)
 501 {
 502         struct nd_region *nd_region = to_nd_region(dev);
 503
 504         return sprintf(buf, "%#lx\n", nd_region->align);
 505 }
 506
 507 static ssize_t align_store(struct device *dev,
 508                 struct device_attribute *attr, const char *buf, size_t len)
 509 {
 510         struct nd_region *nd_region = to_nd_region(dev);
 511         unsigned long val, dpa;
 512         u32 mappings, remainder;
 513         int rc;
 514
 515         rc = kstrtoul(buf, 0, &val);
 516         if (rc)
 517                 return rc;
 518
 519         /*
 520          * Ensure space-align is evenly divisible by the region
 521          * interleave-width because the kernel typically has no facility
 522          * to determine which DIMM(s), dimm-physical-addresses, would
 523          * contribute to the tail capacity in system-physical-address
 524          * space for the namespace.
 525          */
 526         mappings = max_t(u32, 1, nd_region->ndr_mappings);
 527         dpa = div_u64_rem(val, mappings, &remainder);
 528         if (!is_power_of_2(dpa) || dpa < PAGE_SIZE
 529                         || val > region_size(nd_region) || remainder)
 530                 return -EINVAL;
 531
 532         /*
 533          * Given that space allocation consults this value multiple
 534          * times ensure it does not change for the duration of the
 535          * allocation.
 536          */
 537         nvdimm_bus_lock(dev);
 538         nd_region->align = val;
 539         nvdimm_bus_unlock(dev);
 540
 541         return len;
 542 }
 543 static DEVICE_ATTR_RW(align);
 544
 545 static ssize_t region_badblocks_show(struct device *dev,
 546                 struct device_attribute *attr, char *buf)
 547 {
 548         struct nd_region *nd_region = to_nd_region(dev);
 549         ssize_t rc;
 550
 551         device_lock(dev);
 552         if (dev->driver)
 553                 rc = badblocks_show(&nd_region->bb, buf, 0);
 554         else
 555                 rc = -ENXIO;
 556         device_unlock(dev);
 557
 558         return rc;
 559 }
 560 static DEVICE_ATTR(badblocks, 0444, region_badblocks_show, NULL);
 561
 562 static ssize_t resource_show(struct device *dev,
 563                 struct device_attribute *attr, char *buf)
 564 {
 565         struct nd_region *nd_region = to_nd_region(dev);
 566
 567         return sprintf(buf, "%#llx\n", nd_region->ndr_start);
 568 }
 569 static DEVICE_ATTR_ADMIN_RO(resource);
 570
 571 static ssize_t persistence_domain_show(struct device *dev,
 572                 struct device_attribute *attr, char *buf)
 573 {
 574         struct nd_region *nd_region = to_nd_region(dev);
 575
 576         if (test_bit(ND_REGION_PERSIST_CACHE, &nd_region->flags))
 577                 return sprintf(buf, "cpu_cache\n");
 578         else if (test_bit(ND_REGION_PERSIST_MEMCTRL, &nd_region->flags))
 579                 return sprintf(buf, "memory_controller\n");
 580         else
 581                 return sprintf(buf, "\n");
 582 }
 583 static DEVICE_ATTR_RO(persistence_domain);
 584
 585 static struct attribute *nd_region_attributes[] = {
 586         &dev_attr_size.attr,
 587         &dev_attr_align.attr,
 588         &dev_attr_nstype.attr,
 589         &dev_attr_mappings.attr,
 590         &dev_attr_btt_seed.attr,
 591         &dev_attr_pfn_seed.attr,
 592         &dev_attr_dax_seed.attr,
 593         &dev_attr_deep_flush.attr,
 594         &dev_attr_read_only.attr,
 595         &dev_attr_set_cookie.attr,
 596         &dev_attr_available_size.attr,
 597         &dev_attr_max_available_extent.attr,
 598         &dev_attr_namespace_seed.attr,
 599         &dev_attr_init_namespaces.attr,
 600         &dev_attr_badblocks.attr,
 601         &dev_attr_resource.attr,
 602         &dev_attr_persistence_domain.attr,
 603         NULL,
 604 };
 605
 606 static umode_t region_visible(struct kobject *kobj, struct attribute *a, int n)
 607 {
 608         struct device *dev = container_of(kobj, typeof(*dev), kobj);
 609         struct nd_region *nd_region = to_nd_region(dev);
 610         struct nd_interleave_set *nd_set = nd_region->nd_set;
 611         int type = nd_region_to_nstype(nd_region);
 612
 613         if (!is_memory(dev) && a == &dev_attr_pfn_seed.attr)
 614                 return 0;
 615
 616         if (!is_memory(dev) && a == &dev_attr_dax_seed.attr)
 617                 return 0;
 618
 619         if (!is_memory(dev) && a == &dev_attr_badblocks.attr)
 620                 return 0;
 621
 622         if (a == &dev_attr_resource.attr && !is_memory(dev))
 623                 return 0;
 624
 625         if (a == &dev_attr_deep_flush.attr) {
 626                 int has_flush = nvdimm_has_flush(nd_region);
 627
 628                 if (has_flush == 1)
 629                         return a->mode;
 630                 else if (has_flush == 0)
 631                         return 0444;
 632                 else
 633                         return 0;
 634         }
 635
 636         if (a == &dev_attr_persistence_domain.attr) {
 637                 if ((nd_region->flags & (BIT(ND_REGION_PERSIST_CACHE)
 638                                         | BIT(ND_REGION_PERSIST_MEMCTRL))) == 0)
 639                         return 0;
 640                 return a->mode;
 641         }
 642
 643         if (a == &dev_attr_align.attr)
 644                 return a->mode;
 645
 646         if (a != &dev_attr_set_cookie.attr
 647                         && a != &dev_attr_available_size.attr)
 648                 return a->mode;
 649
 650         if (type == ND_DEVICE_NAMESPACE_PMEM &&
 651             a == &dev_attr_available_size.attr)
 652                 return a->mode;
 653         else if (is_memory(dev) && nd_set)
 654                 return a->mode;
 655
 656         return 0;
 657 }
 658
 659 static ssize_t mappingN(struct device *dev, char *buf, int n)
 660 {
 661         struct nd_region *nd_region = to_nd_region(dev);
 662         struct nd_mapping *nd_mapping;
 663         struct nvdimm *nvdimm;
 664
 665         if (n >= nd_region->ndr_mappings)
 666                 return -ENXIO;
 667         nd_mapping = &nd_region->mapping[n];
 668         nvdimm = nd_mapping->nvdimm;
 669
 670         return sprintf(buf, "%s,%llu,%llu,%d\n", dev_name(&nvdimm->dev),
 671                         nd_mapping->start, nd_mapping->size,
 672                         nd_mapping->position);
 673 }
 674
 675 #define REGION_MAPPING(idx) \
 676 static ssize_t mapping##idx##_show(struct device *dev,          \
 677                 struct device_attribute *attr, char *buf)       \
 678 {                                                               \
 679         return mappingN(dev, buf, idx);                         \
 680 }                                                               \
 681 static DEVICE_ATTR_RO(mapping##idx)
 682
 683 /*
 684  * 32 should be enough for a while, even in the presence of socket
 685  * interleave a 32-way interleave set is a degenerate case.
 686  */
 687 REGION_MAPPING(0);
 688 REGION_MAPPING(1);
 689 REGION_MAPPING(2);
 690 REGION_MAPPING(3);
 691 REGION_MAPPING(4);
 692 REGION_MAPPING(5);
 693 REGION_MAPPING(6);
 694 REGION_MAPPING(7);
 695 REGION_MAPPING(8);
 696 REGION_MAPPING(9);
 697 REGION_MAPPING(10);
 698 REGION_MAPPING(11);
 699 REGION_MAPPING(12);
 700 REGION_MAPPING(13);
 701 REGION_MAPPING(14);
 702 REGION_MAPPING(15);
 703 REGION_MAPPING(16);
 704 REGION_MAPPING(17);
 705 REGION_MAPPING(18);
 706 REGION_MAPPING(19);
 707 REGION_MAPPING(20);
 708 REGION_MAPPING(21);
 709 REGION_MAPPING(22);
 710 REGION_MAPPING(23);
 711 REGION_MAPPING(24);
 712 REGION_MAPPING(25);
 713 REGION_MAPPING(26);
 714 REGION_MAPPING(27);
 715 REGION_MAPPING(28);
 716 REGION_MAPPING(29);
 717 REGION_MAPPING(30);
 718 REGION_MAPPING(31);
 719
 720 static umode_t mapping_visible(struct kobject *kobj, struct attribute *a, int n)
 721 {
 722         struct device *dev = container_of(kobj, struct device, kobj);
 723         struct nd_region *nd_region = to_nd_region(dev);
 724
 725         if (n < nd_region->ndr_mappings)
 726                 return a->mode;
 727         return 0;
 728 }
 729
 730 static struct attribute *mapping_attributes[] = {
 731         &dev_attr_mapping0.attr,
 732         &dev_attr_mapping1.attr,
 733         &dev_attr_mapping2.attr,
 734         &dev_attr_mapping3.attr,
 735         &dev_attr_mapping4.attr,
 736         &dev_attr_mapping5.attr,
 737         &dev_attr_mapping6.attr,
 738         &dev_attr_mapping7.attr,
 739         &dev_attr_mapping8.attr,
 740         &dev_attr_mapping9.attr,
 741         &dev_attr_mapping10.attr,
 742         &dev_attr_mapping11.attr,
 743         &dev_attr_mapping12.attr,
 744         &dev_attr_mapping13.attr,
 745         &dev_attr_mapping14.attr,
 746         &dev_attr_mapping15.attr,
 747         &dev_attr_mapping16.attr,
 748         &dev_attr_mapping17.attr,
 749         &dev_attr_mapping18.attr,
 750         &dev_attr_mapping19.attr,
 751         &dev_attr_mapping20.attr,
 752         &dev_attr_mapping21.attr,
 753         &dev_attr_mapping22.attr,
 754         &dev_attr_mapping23.attr,
 755         &dev_attr_mapping24.attr,
 756         &dev_attr_mapping25.attr,
 757         &dev_attr_mapping26.attr,
 758         &dev_attr_mapping27.attr,
 759         &dev_attr_mapping28.attr,
 760         &dev_attr_mapping29.attr,
 761         &dev_attr_mapping30.attr,
 762         &dev_attr_mapping31.attr,
 763         NULL,
 764 };
 765
 766 static const struct attribute_group nd_mapping_attribute_group = {
 767         .is_visible = mapping_visible,
 768         .attrs = mapping_attributes,
 769 };
 770
 771 static const struct attribute_group nd_region_attribute_group = {
 772         .attrs = nd_region_attributes,
 773         .is_visible = region_visible,
 774 };
 775
 776 static const struct attribute_group *nd_region_attribute_groups[] = {
 777         &nd_device_attribute_group,
 778         &nd_region_attribute_group,
 779         &nd_numa_attribute_group,
 780         &nd_mapping_attribute_group,
 781         NULL,
 782 };
 783
 784 static const struct device_type nd_pmem_device_type = {
 785         .name = "nd_pmem",
 786         .release = nd_region_release,
 787         .groups = nd_region_attribute_groups,
 788 };
 789
 790 static const struct device_type nd_volatile_device_type = {
 791         .name = "nd_volatile",
 792         .release = nd_region_release,
 793         .groups = nd_region_attribute_groups,
 794 };
 795
 796 bool is_nd_pmem(struct device *dev)
 797 {
 798         return dev ? dev->type == &nd_pmem_device_type : false;
 799 }
 800
 801 bool is_nd_volatile(struct device *dev)
 802 {
 803         return dev ? dev->type == &nd_volatile_device_type : false;
 804 }
 805
 806 u64 nd_region_interleave_set_cookie(struct nd_region *nd_region,
 807                 struct nd_namespace_index *nsindex)
 808 {
 809         struct nd_interleave_set *nd_set = nd_region->nd_set;
 810
 811         if (!nd_set)
 812                 return 0;
 813
 814         if (nsindex && __le16_to_cpu(nsindex->major) == 1
 815                         && __le16_to_cpu(nsindex->minor) == 1)
 816                 return nd_set->cookie1;
 817         return nd_set->cookie2;
 818 }
 819
 820 u64 nd_region_interleave_set_altcookie(struct nd_region *nd_region)
 821 {
 822         struct nd_interleave_set *nd_set = nd_region->nd_set;
 823
 824         if (nd_set)
 825                 return nd_set->altcookie;
 826         return 0;
 827 }
 828
 829 void nd_mapping_free_labels(struct nd_mapping *nd_mapping)
 830 {
 831         struct nd_label_ent *label_ent, *e;
 832
 833         lockdep_assert_held(&nd_mapping->lock);
 834         list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
 835                 list_del(&label_ent->list);
 836                 kfree(label_ent);
 837         }
 838 }
 839
 840 /*
 841  * When a namespace is activated create new seeds for the next
 842  * namespace, or namespace-personality to be configured.
 843  */
 844 void nd_region_advance_seeds(struct nd_region *nd_region, struct device *dev)
 845 {
 846         nvdimm_bus_lock(dev);
 847         if (nd_region->ns_seed == dev) {
 848                 nd_region_create_ns_seed(nd_region);
 849         } else if (is_nd_btt(dev)) {
 850                 struct nd_btt *nd_btt = to_nd_btt(dev);
 851
 852                 if (nd_region->btt_seed == dev)
 853                         nd_region_create_btt_seed(nd_region);
 854                 if (nd_region->ns_seed == &nd_btt->ndns->dev)
 855                         nd_region_create_ns_seed(nd_region);
 856         } else if (is_nd_pfn(dev)) {
 857                 struct nd_pfn *nd_pfn = to_nd_pfn(dev);
 858
 859                 if (nd_region->pfn_seed == dev)
 860                         nd_region_create_pfn_seed(nd_region);
 861                 if (nd_region->ns_seed == &nd_pfn->ndns->dev)
 862                         nd_region_create_ns_seed(nd_region);
 863         } else if (is_nd_dax(dev)) {
 864                 struct nd_dax *nd_dax = to_nd_dax(dev);
 865
 866                 if (nd_region->dax_seed == dev)
 867                         nd_region_create_dax_seed(nd_region);
 868                 if (nd_region->ns_seed == &nd_dax->nd_pfn.ndns->dev)
 869                         nd_region_create_ns_seed(nd_region);
 870         }
 871         nvdimm_bus_unlock(dev);
 872 }
 873
 874 /**
 875  * nd_region_acquire_lane - allocate and lock a lane
 876  * @nd_region: region id and number of lanes possible
 877  *
 878  * A lane correlates to a BLK-data-window and/or a log slot in the BTT.
 879  * We optimize for the common case where there are 256 lanes, one
 880  * per-cpu.  For larger systems we need to lock to share lanes.  For now
 881  * this implementation assumes the cost of maintaining an allocator for
 882  * free lanes is on the order of the lock hold time, so it implements a
 883  * static lane = cpu % num_lanes mapping.
 884  *
 885  * In the case of a BTT instance on top of a BLK namespace a lane may be
 886  * acquired recursively.  We lock on the first instance.
 887  *
 888  * In the case of a BTT instance on top of PMEM, we only acquire a lane
 889  * for the BTT metadata updates.
 890  */
 891 unsigned int nd_region_acquire_lane(struct nd_region *nd_region)
 892 {
 893         unsigned int cpu, lane;
 894
 895         cpu = get_cpu();
 896         if (nd_region->num_lanes < nr_cpu_ids) {
 897                 struct nd_percpu_lane *ndl_lock, *ndl_count;
 898
 899                 lane = cpu % nd_region->num_lanes;
 900                 ndl_count = per_cpu_ptr(nd_region->lane, cpu);
 901                 ndl_lock = per_cpu_ptr(nd_region->lane, lane);
 902                 if (ndl_count->count++ == 0)
 903                         spin_lock(&ndl_lock->lock);
 904         } else
 905                 lane = cpu;
 906
 907         return lane;
 908 }
 909 EXPORT_SYMBOL(nd_region_acquire_lane);
 910
 911 void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane)
 912 {
 913         if (nd_region->num_lanes < nr_cpu_ids) {
 914                 unsigned int cpu = get_cpu();
 915                 struct nd_percpu_lane *ndl_lock, *ndl_count;
 916
 917                 ndl_count = per_cpu_ptr(nd_region->lane, cpu);
 918                 ndl_lock = per_cpu_ptr(nd_region->lane, lane);
 919                 if (--ndl_count->count == 0)
 920                         spin_unlock(&ndl_lock->lock);
 921                 put_cpu();
 922         }
 923         put_cpu();
 924 }
 925 EXPORT_SYMBOL(nd_region_release_lane);
 926
 927 /*
 928  * PowerPC requires this alignment for memremap_pages(). All other archs
 929  * should be ok with SUBSECTION_SIZE (see memremap_compat_align()).
 930  */
 931 #define MEMREMAP_COMPAT_ALIGN_MAX SZ_16M
 932
 933 static unsigned long default_align(struct nd_region *nd_region)
 934 {
 935         unsigned long align;
 936         u32 remainder;
 937         int mappings;
 938
 939         align = MEMREMAP_COMPAT_ALIGN_MAX;
 940         if (nd_region->ndr_size < MEMREMAP_COMPAT_ALIGN_MAX)
 941                 align = PAGE_SIZE;
 942
 943         mappings = max_t(u16, 1, nd_region->ndr_mappings);
 944         div_u64_rem(align, mappings, &remainder);
 945         if (remainder)
 946                 align *= mappings;
 947
 948         return align;
 949 }
 950
 951 static struct lock_class_key nvdimm_region_key;
 952
 953 static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
 954                 struct nd_region_desc *ndr_desc,
 955                 const struct device_type *dev_type, const char *caller)
 956 {
 957         struct nd_region *nd_region;
 958         struct device *dev;
 959         unsigned int i;
 960         int ro = 0;
 961
 962         for (i = 0; i < ndr_desc->num_mappings; i++) {
 963                 struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
 964                 struct nvdimm *nvdimm = mapping->nvdimm;
 965
 966                 if ((mapping->start | mapping->size) % PAGE_SIZE) {
 967                         dev_err(&nvdimm_bus->dev,
 968                                 "%s: %s mapping%d is not %ld aligned\n",
 969                                 caller, dev_name(&nvdimm->dev), i, PAGE_SIZE);
 970                         return NULL;
 971                 }
 972
 973                 if (test_bit(NDD_UNARMED, &nvdimm->flags))
 974                         ro = 1;
 975
 976         }
 977
 978         nd_region =
 979                 kzalloc(struct_size(nd_region, mapping, ndr_desc->num_mappings),
 980                         GFP_KERNEL);
 981
 982         if (!nd_region)
 983                 return NULL;
 984         /* CXL pre-assigns memregion ids before creating nvdimm regions */
 985         if (test_bit(ND_REGION_CXL, &ndr_desc->flags)) {
 986                 nd_region->id = ndr_desc->memregion;
 987         } else {
 988                 nd_region->id = memregion_alloc(GFP_KERNEL);
 989                 if (nd_region->id < 0)
 990                         goto err_id;
 991         }
 992
 993         nd_region->lane = alloc_percpu(struct nd_percpu_lane);
 994         if (!nd_region->lane)
 995                 goto err_percpu;
 996
 997         for (i = 0; i < nr_cpu_ids; i++) {
 998                 struct nd_percpu_lane *ndl;
 999
1000                 ndl = per_cpu_ptr(nd_region->lane, i);
1001                 spin_lock_init(&ndl->lock);
1002                 ndl->count = 0;
1003         }
1004
1005         for (i = 0; i < ndr_desc->num_mappings; i++) {
1006                 struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
1007                 struct nvdimm *nvdimm = mapping->nvdimm;
1008
1009                 nd_region->mapping[i].nvdimm = nvdimm;
1010                 nd_region->mapping[i].start = mapping->start;
1011                 nd_region->mapping[i].size = mapping->size;
1012                 nd_region->mapping[i].position = mapping->position;
1013                 INIT_LIST_HEAD(&nd_region->mapping[i].labels);
1014                 mutex_init(&nd_region->mapping[i].lock);
1015
1016                 get_device(&nvdimm->dev);
1017         }
1018         nd_region->ndr_mappings = ndr_desc->num_mappings;
1019         nd_region->provider_data = ndr_desc->provider_data;
1020         nd_region->nd_set = ndr_desc->nd_set;
1021         nd_region->num_lanes = ndr_desc->num_lanes;
1022         nd_region->flags = ndr_desc->flags;
1023         nd_region->ro = ro;
1024         nd_region->numa_node = ndr_desc->numa_node;
1025         nd_region->target_node = ndr_desc->target_node;
1026         ida_init(&nd_region->ns_ida);
1027         ida_init(&nd_region->btt_ida);
1028         ida_init(&nd_region->pfn_ida);
1029         ida_init(&nd_region->dax_ida);
1030         dev = &nd_region->dev;
1031         dev_set_name(dev, "region%d", nd_region->id);
1032         dev->parent = &nvdimm_bus->dev;
1033         dev->type = dev_type;
1034         dev->groups = ndr_desc->attr_groups;
1035         dev->of_node = ndr_desc->of_node;
1036         nd_region->ndr_size = resource_size(ndr_desc->res);
1037         nd_region->ndr_start = ndr_desc->res->start;
1038         nd_region->align = default_align(nd_region);
1039         if (ndr_desc->flush)
1040                 nd_region->flush = ndr_desc->flush;
1041         else
1042                 nd_region->flush = NULL;
1043
1044         device_initialize(dev);
1045         lockdep_set_class(&dev->mutex, &nvdimm_region_key);
1046         nd_device_register(dev);
1047
1048         return nd_region;
1049
1050 err_percpu:
1051         if (!test_bit(ND_REGION_CXL, &ndr_desc->flags))
1052                 memregion_free(nd_region->id);
1053 err_id:
1054         kfree(nd_region);
1055         return NULL;
1056 }
1057
1058 struct nd_region *nvdimm_pmem_region_create(struct nvdimm_bus *nvdimm_bus,
1059                 struct nd_region_desc *ndr_desc)
1060 {
1061         ndr_desc->num_lanes = ND_MAX_LANES;
1062         return nd_region_create(nvdimm_bus, ndr_desc, &nd_pmem_device_type,
1063                         __func__);
1064 }
1065 EXPORT_SYMBOL_GPL(nvdimm_pmem_region_create);
1066
1067 struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus,
1068                 struct nd_region_desc *ndr_desc)
1069 {
1070         ndr_desc->num_lanes = ND_MAX_LANES;
1071         return nd_region_create(nvdimm_bus, ndr_desc, &nd_volatile_device_type,
1072                         __func__);
1073 }
1074 EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create);
1075
1076 void nvdimm_region_delete(struct nd_region *nd_region)
1077 {
1078         if (nd_region)
1079                 nd_device_unregister(&nd_region->dev, ND_SYNC);
1080 }
1081 EXPORT_SYMBOL_GPL(nvdimm_region_delete);
1082
1083 int nvdimm_flush(struct nd_region *nd_region, struct bio *bio)
1084 {
1085         int rc = 0;
1086
1087         if (!nd_region->flush)
1088                 rc = generic_nvdimm_flush(nd_region);
1089         else {
1090                 if (nd_region->flush(nd_region, bio))
1091                         rc = -EIO;
1092         }
1093
1094         return rc;
1095 }
1096 /**
1097  * generic_nvdimm_flush() - flush any posted write queues between the cpu and pmem media
1098  * @nd_region: interleaved pmem region
1099  */
1100 int generic_nvdimm_flush(struct nd_region *nd_region)
1101 {
1102         struct nd_region_data *ndrd = dev_get_drvdata(&nd_region->dev);
1103         int i, idx;
1104
1105         /*
1106          * Try to encourage some diversity in flush hint addresses
1107          * across cpus assuming a limited number of flush hints.
1108          */
1109         idx = this_cpu_read(flush_idx);
1110         idx = this_cpu_add_return(flush_idx, hash_32(current->pid + idx, 8));
1111
1112         /*
1113          * The pmem_wmb() is needed to 'sfence' all
1114          * previous writes such that they are architecturally visible for
1115          * the platform buffer flush. Note that we've already arranged for pmem
1116          * writes to avoid the cache via memcpy_flushcache().  The final
1117          * wmb() ensures ordering for the NVDIMM flush write.
1118          */
1119         pmem_wmb();
1120         for (i = 0; i < nd_region->ndr_mappings; i++)
1121                 if (ndrd_get_flush_wpq(ndrd, i, 0))
1122                         writeq(1, ndrd_get_flush_wpq(ndrd, i, idx));
1123         wmb();
1124
1125         return 0;
1126 }
1127 EXPORT_SYMBOL_GPL(nvdimm_flush);
1128
1129 /**
1130  * nvdimm_has_flush - determine write flushing requirements
1131  * @nd_region: interleaved pmem region
1132  *
1133  * Returns 1 if writes require flushing
1134  * Returns 0 if writes do not require flushing
1135  * Returns -ENXIO if flushing capability can not be determined
1136  */
1137 int nvdimm_has_flush(struct nd_region *nd_region)
1138 {
1139         int i;
1140
1141         /* no nvdimm or pmem api == flushing capability unknown */
1142         if (nd_region->ndr_mappings == 0
1143                         || !IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API))
1144                 return -ENXIO;
1145
1146         /* Test if an explicit flush function is defined */
1147         if (test_bit(ND_REGION_ASYNC, &nd_region->flags) && nd_region->flush)
1148                 return 1;
1149
1150         /* Test if any flush hints for the region are available */
1151         for (i = 0; i < nd_region->ndr_mappings; i++) {
1152                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
1153                 struct nvdimm *nvdimm = nd_mapping->nvdimm;
1154
1155                 /* flush hints present / available */
1156                 if (nvdimm->num_flush)
1157                         return 1;
1158         }
1159
1160         /*
1161          * The platform defines dimm devices without hints nor explicit flush,
1162          * assume platform persistence mechanism like ADR
1163          */
1164         return 0;
1165 }
1166 EXPORT_SYMBOL_GPL(nvdimm_has_flush);
1167
1168 int nvdimm_has_cache(struct nd_region *nd_region)
1169 {
1170         return is_nd_pmem(&nd_region->dev) &&
1171                 !test_bit(ND_REGION_PERSIST_CACHE, &nd_region->flags);
1172 }
1173 EXPORT_SYMBOL_GPL(nvdimm_has_cache);
1174
1175 bool is_nvdimm_sync(struct nd_region *nd_region)
1176 {
1177         if (is_nd_volatile(&nd_region->dev))
1178                 return true;
1179
1180         return is_nd_pmem(&nd_region->dev) &&
1181                 !test_bit(ND_REGION_ASYNC, &nd_region->flags);
1182 }
1183 EXPORT_SYMBOL_GPL(is_nvdimm_sync);
1184
1185 struct conflict_context {
1186         struct nd_region *nd_region;
1187         resource_size_t start, size;
1188 };
1189
1190 static int region_conflict(struct device *dev, void *data)
1191 {
1192         struct nd_region *nd_region;
1193         struct conflict_context *ctx = data;
1194         resource_size_t res_end, region_end, region_start;
1195
1196         if (!is_memory(dev))
1197                 return 0;
1198
1199         nd_region = to_nd_region(dev);
1200         if (nd_region == ctx->nd_region)
1201                 return 0;
1202
1203         res_end = ctx->start + ctx->size;
1204         region_start = nd_region->ndr_start;
1205         region_end = region_start + nd_region->ndr_size;
1206         if (ctx->start >= region_start && ctx->start < region_end)
1207                 return -EBUSY;
1208         if (res_end > region_start && res_end <= region_end)
1209                 return -EBUSY;
1210         return 0;
1211 }
1212
1213 int nd_region_conflict(struct nd_region *nd_region, resource_size_t start,
1214                 resource_size_t size)
1215 {
1216         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
1217         struct conflict_context ctx = {
1218                 .nd_region = nd_region,
1219                 .start = start,
1220                 .size = size,
1221         };
1222
1223         return device_for_each_child(&nvdimm_bus->dev, &ctx, region_conflict);
1224 }