drivers/nvdimm/pmem.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Persistent Memory Driver
   4  *
   5  * Copyright (c) 2014-2015, Intel Corporation.
   6  * Copyright (c) 2015, Christoph Hellwig <[email protected]>.
   7  * Copyright (c) 2015, Boaz Harrosh <[email protected]>.
   8  */
   9
  10 #include <linux/blkdev.h>
  11 #include <linux/pagemap.h>
  12 #include <linux/hdreg.h>
  13 #include <linux/init.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/set_memory.h>
  16 #include <linux/module.h>
  17 #include <linux/moduleparam.h>
  18 #include <linux/badblocks.h>
  19 #include <linux/memremap.h>
  20 #include <linux/vmalloc.h>
  21 #include <linux/blk-mq.h>
  22 #include <linux/pfn_t.h>
  23 #include <linux/slab.h>
  24 #include <linux/uio.h>
  25 #include <linux/dax.h>
  26 #include <linux/nd.h>
  27 #include <linux/mm.h>
  28 #include <asm/cacheflush.h>
  29 #include "pmem.h"
  30 #include "btt.h"
  31 #include "pfn.h"
  32 #include "nd.h"
  33
  34 static struct device *to_dev(struct pmem_device *pmem)
  35 {
  36         /*
  37          * nvdimm bus services need a 'dev' parameter, and we record the device
  38          * at init in bb.dev.
  39          */
  40         return pmem->bb.dev;
  41 }
  42
  43 static struct nd_region *to_region(struct pmem_device *pmem)
  44 {
  45         return to_nd_region(to_dev(pmem)->parent);
  46 }
  47
  48 static void hwpoison_clear(struct pmem_device *pmem,
  49                 phys_addr_t phys, unsigned int len)
  50 {
  51         unsigned long pfn_start, pfn_end, pfn;
  52
  53         /* only pmem in the linear map supports HWPoison */
  54         if (is_vmalloc_addr(pmem->virt_addr))
  55                 return;
  56
  57         pfn_start = PHYS_PFN(phys);
  58         pfn_end = pfn_start + PHYS_PFN(len);
  59         for (pfn = pfn_start; pfn < pfn_end; pfn++) {
  60                 struct page *page = pfn_to_page(pfn);
  61
  62                 /*
  63                  * Note, no need to hold a get_dev_pagemap() reference
  64                  * here since we're in the driver I/O path and
  65                  * outstanding I/O requests pin the dev_pagemap.
  66                  */
  67                 if (test_and_clear_pmem_poison(page))
  68                         clear_mce_nospec(pfn);
  69         }
  70 }
  71
  72 static blk_status_t pmem_clear_poison(struct pmem_device *pmem,
  73                 phys_addr_t offset, unsigned int len)
  74 {
  75         struct device *dev = to_dev(pmem);
  76         sector_t sector;
  77         long cleared;
  78         blk_status_t rc = BLK_STS_OK;
  79
  80         sector = (offset - pmem->data_offset) / 512;
  81
  82         cleared = nvdimm_clear_poison(dev, pmem->phys_addr + offset, len);
  83         if (cleared < len)
  84                 rc = BLK_STS_IOERR;
  85         if (cleared > 0 && cleared / 512) {
  86                 hwpoison_clear(pmem, pmem->phys_addr + offset, cleared);
  87                 cleared /= 512;
  88                 dev_dbg(dev, "%#llx clear %ld sector%s\n",
  89                                 (unsigned long long) sector, cleared,
  90                                 cleared > 1 ? "s" : "");
  91                 badblocks_clear(&pmem->bb, sector, cleared);
  92                 if (pmem->bb_state)
  93                         sysfs_notify_dirent(pmem->bb_state);
  94         }
  95
  96         arch_invalidate_pmem(pmem->virt_addr + offset, len);
  97
  98         return rc;
  99 }
 100
 101 static void write_pmem(void *pmem_addr, struct page *page,
 102                 unsigned int off, unsigned int len)
 103 {
 104         unsigned int chunk;
 105         void *mem;
 106
 107         while (len) {
 108                 mem = kmap_atomic(page);
 109                 chunk = min_t(unsigned int, len, PAGE_SIZE - off);
 110                 memcpy_flushcache(pmem_addr, mem + off, chunk);
 111                 kunmap_atomic(mem);
 112                 len -= chunk;
 113                 off = 0;
 114                 page++;
 115                 pmem_addr += chunk;
 116         }
 117 }
 118
 119 static blk_status_t read_pmem(struct page *page, unsigned int off,
 120                 void *pmem_addr, unsigned int len)
 121 {
 122         unsigned int chunk;
 123         unsigned long rem;
 124         void *mem;
 125
 126         while (len) {
 127                 mem = kmap_atomic(page);
 128                 chunk = min_t(unsigned int, len, PAGE_SIZE - off);
 129                 rem = copy_mc_to_kernel(mem + off, pmem_addr, chunk);
 130                 kunmap_atomic(mem);
 131                 if (rem)
 132                         return BLK_STS_IOERR;
 133                 len -= chunk;
 134                 off = 0;
 135                 page++;
 136                 pmem_addr += chunk;
 137         }
 138         return BLK_STS_OK;
 139 }
 140
 141 static blk_status_t pmem_do_read(struct pmem_device *pmem,
 142                         struct page *page, unsigned int page_off,
 143                         sector_t sector, unsigned int len)
 144 {
 145         blk_status_t rc;
 146         phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
 147         void *pmem_addr = pmem->virt_addr + pmem_off;
 148
 149         if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
 150                 return BLK_STS_IOERR;
 151
 152         rc = read_pmem(page, page_off, pmem_addr, len);
 153         flush_dcache_page(page);
 154         return rc;
 155 }
 156
 157 static blk_status_t pmem_do_write(struct pmem_device *pmem,
 158                         struct page *page, unsigned int page_off,
 159                         sector_t sector, unsigned int len)
 160 {
 161         blk_status_t rc = BLK_STS_OK;
 162         bool bad_pmem = false;
 163         phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
 164         void *pmem_addr = pmem->virt_addr + pmem_off;
 165
 166         if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
 167                 bad_pmem = true;
 168
 169         /*
 170          * Note that we write the data both before and after
 171          * clearing poison.  The write before clear poison
 172          * handles situations where the latest written data is
 173          * preserved and the clear poison operation simply marks
 174          * the address range as valid without changing the data.
 175          * In this case application software can assume that an
 176          * interrupted write will either return the new good
 177          * data or an error.
 178          *
 179          * However, if pmem_clear_poison() leaves the data in an
 180          * indeterminate state we need to perform the write
 181          * after clear poison.
 182          */
 183         flush_dcache_page(page);
 184         write_pmem(pmem_addr, page, page_off, len);
 185         if (unlikely(bad_pmem)) {
 186                 rc = pmem_clear_poison(pmem, pmem_off, len);
 187                 write_pmem(pmem_addr, page, page_off, len);
 188         }
 189
 190         return rc;
 191 }
 192
 193 static void pmem_submit_bio(struct bio *bio)
 194 {
 195         int ret = 0;
 196         blk_status_t rc = 0;
 197         bool do_acct;
 198         unsigned long start;
 199         struct bio_vec bvec;
 200         struct bvec_iter iter;
 201         struct pmem_device *pmem = bio->bi_bdev->bd_disk->private_data;
 202         struct nd_region *nd_region = to_region(pmem);
 203
 204         if (bio->bi_opf & REQ_PREFLUSH)
 205                 ret = nvdimm_flush(nd_region, bio);
 206
 207         do_acct = blk_queue_io_stat(bio->bi_bdev->bd_disk->queue);
 208         if (do_acct)
 209                 start = bio_start_io_acct(bio);
 210         bio_for_each_segment(bvec, bio, iter) {
 211                 if (op_is_write(bio_op(bio)))
 212                         rc = pmem_do_write(pmem, bvec.bv_page, bvec.bv_offset,
 213                                 iter.bi_sector, bvec.bv_len);
 214                 else
 215                         rc = pmem_do_read(pmem, bvec.bv_page, bvec.bv_offset,
 216                                 iter.bi_sector, bvec.bv_len);
 217                 if (rc) {
 218                         bio->bi_status = rc;
 219                         break;
 220                 }
 221         }
 222         if (do_acct)
 223                 bio_end_io_acct(bio, start);
 224
 225         if (bio->bi_opf & REQ_FUA)
 226                 ret = nvdimm_flush(nd_region, bio);
 227
 228         if (ret)
 229                 bio->bi_status = errno_to_blk_status(ret);
 230
 231         bio_endio(bio);
 232 }
 233
 234 static int pmem_rw_page(struct block_device *bdev, sector_t sector,
 235                        struct page *page, unsigned int op)
 236 {
 237         struct pmem_device *pmem = bdev->bd_disk->private_data;
 238         blk_status_t rc;
 239
 240         if (op_is_write(op))
 241                 rc = pmem_do_write(pmem, page, 0, sector, thp_size(page));
 242         else
 243                 rc = pmem_do_read(pmem, page, 0, sector, thp_size(page));
 244         /*
 245          * The ->rw_page interface is subtle and tricky.  The core
 246          * retries on any error, so we can only invoke page_endio() in
 247          * the successful completion case.  Otherwise, we'll see crashes
 248          * caused by double completion.
 249          */
 250         if (rc == 0)
 251                 page_endio(page, op_is_write(op), 0);
 252
 253         return blk_status_to_errno(rc);
 254 }
 255
 256 /* see "strong" declaration in tools/testing/nvdimm/pmem-dax.c */
 257 __weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
 258                 long nr_pages, void **kaddr, pfn_t *pfn)
 259 {
 260         resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
 261
 262         if (unlikely(is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) / 512,
 263                                         PFN_PHYS(nr_pages))))
 264                 return -EIO;
 265
 266         if (kaddr)
 267                 *kaddr = pmem->virt_addr + offset;
 268         if (pfn)
 269                 *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
 270
 271         /*
 272          * If badblocks are present, limit known good range to the
 273          * requested range.
 274          */
 275         if (unlikely(pmem->bb.count))
 276                 return nr_pages;
 277         return PHYS_PFN(pmem->size - pmem->pfn_pad - offset);
 278 }
 279
 280 static const struct block_device_operations pmem_fops = {
 281         .owner =                THIS_MODULE,
 282         .submit_bio =           pmem_submit_bio,
 283         .rw_page =              pmem_rw_page,
 284 };
 285
 286 static int pmem_dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
 287                                     size_t nr_pages)
 288 {
 289         struct pmem_device *pmem = dax_get_private(dax_dev);
 290
 291         return blk_status_to_errno(pmem_do_write(pmem, ZERO_PAGE(0), 0,
 292                                    PFN_PHYS(pgoff) >> SECTOR_SHIFT,
 293                                    PAGE_SIZE));
 294 }
 295
 296 static long pmem_dax_direct_access(struct dax_device *dax_dev,
 297                 pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn)
 298 {
 299         struct pmem_device *pmem = dax_get_private(dax_dev);
 300
 301         return __pmem_direct_access(pmem, pgoff, nr_pages, kaddr, pfn);
 302 }
 303
 304 /*
 305  * Use the 'no check' versions of copy_from_iter_flushcache() and
 306  * copy_mc_to_iter() to bypass HARDENED_USERCOPY overhead. Bounds
 307  * checking, both file offset and device offset, is handled by
 308  * dax_iomap_actor()
 309  */
 310 static size_t pmem_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff,
 311                 void *addr, size_t bytes, struct iov_iter *i)
 312 {
 313         return _copy_from_iter_flushcache(addr, bytes, i);
 314 }
 315
 316 static size_t pmem_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff,
 317                 void *addr, size_t bytes, struct iov_iter *i)
 318 {
 319         return _copy_mc_to_iter(addr, bytes, i);
 320 }
 321
 322 static const struct dax_operations pmem_dax_ops = {
 323         .direct_access = pmem_dax_direct_access,
 324         .dax_supported = generic_fsdax_supported,
 325         .copy_from_iter = pmem_copy_from_iter,
 326         .copy_to_iter = pmem_copy_to_iter,
 327         .zero_page_range = pmem_dax_zero_page_range,
 328 };
 329
 330 static ssize_t write_cache_show(struct device *dev,
 331                 struct device_attribute *attr, char *buf)
 332 {
 333         struct pmem_device *pmem = dev_to_disk(dev)->private_data;
 334
 335         return sprintf(buf, "%d\n", !!dax_write_cache_enabled(pmem->dax_dev));
 336 }
 337
 338 static ssize_t write_cache_store(struct device *dev,
 339                 struct device_attribute *attr, const char *buf, size_t len)
 340 {
 341         struct pmem_device *pmem = dev_to_disk(dev)->private_data;
 342         bool write_cache;
 343         int rc;
 344
 345         rc = strtobool(buf, &write_cache);
 346         if (rc)
 347                 return rc;
 348         dax_write_cache(pmem->dax_dev, write_cache);
 349         return len;
 350 }
 351 static DEVICE_ATTR_RW(write_cache);
 352
 353 static umode_t dax_visible(struct kobject *kobj, struct attribute *a, int n)
 354 {
 355 #ifndef CONFIG_ARCH_HAS_PMEM_API
 356         if (a == &dev_attr_write_cache.attr)
 357                 return 0;
 358 #endif
 359         return a->mode;
 360 }
 361
 362 static struct attribute *dax_attributes[] = {
 363         &dev_attr_write_cache.attr,
 364         NULL,
 365 };
 366
 367 static const struct attribute_group dax_attribute_group = {
 368         .name           = "dax",
 369         .attrs          = dax_attributes,
 370         .is_visible     = dax_visible,
 371 };
 372
 373 static const struct attribute_group *pmem_attribute_groups[] = {
 374         &dax_attribute_group,
 375         NULL,
 376 };
 377
 378 static void pmem_release_disk(void *__pmem)
 379 {
 380         struct pmem_device *pmem = __pmem;
 381
 382         kill_dax(pmem->dax_dev);
 383         put_dax(pmem->dax_dev);
 384         del_gendisk(pmem->disk);
 385
 386         blk_cleanup_disk(pmem->disk);
 387 }
 388
 389 static int pmem_attach_disk(struct device *dev,
 390                 struct nd_namespace_common *ndns)
 391 {
 392         struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
 393         struct nd_region *nd_region = to_nd_region(dev->parent);
 394         int nid = dev_to_node(dev), fua;
 395         struct resource *res = &nsio->res;
 396         struct range bb_range;
 397         struct nd_pfn *nd_pfn = NULL;
 398         struct dax_device *dax_dev;
 399         struct nd_pfn_sb *pfn_sb;
 400         struct pmem_device *pmem;
 401         struct request_queue *q;
 402         struct gendisk *disk;
 403         void *addr;
 404         int rc;
 405         unsigned long flags = 0UL;
 406
 407         pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
 408         if (!pmem)
 409                 return -ENOMEM;
 410
 411         rc = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
 412         if (rc)
 413                 return rc;
 414
 415         /* while nsio_rw_bytes is active, parse a pfn info block if present */
 416         if (is_nd_pfn(dev)) {
 417                 nd_pfn = to_nd_pfn(dev);
 418                 rc = nvdimm_setup_pfn(nd_pfn, &pmem->pgmap);
 419                 if (rc)
 420                         return rc;
 421         }
 422
 423         /* we're attaching a block device, disable raw namespace access */
 424         devm_namespace_disable(dev, ndns);
 425
 426         dev_set_drvdata(dev, pmem);
 427         pmem->phys_addr = res->start;
 428         pmem->size = resource_size(res);
 429         fua = nvdimm_has_flush(nd_region);
 430         if (!IS_ENABLED(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) || fua < 0) {
 431                 dev_warn(dev, "unable to guarantee persistence of writes\n");
 432                 fua = 0;
 433         }
 434
 435         if (!devm_request_mem_region(dev, res->start, resource_size(res),
 436                                 dev_name(&ndns->dev))) {
 437                 dev_warn(dev, "could not reserve region %pR\n", res);
 438                 return -EBUSY;
 439         }
 440
 441         disk = blk_alloc_disk(nid);
 442         if (!disk)
 443                 return -ENOMEM;
 444         q = disk->queue;
 445
 446         pmem->disk = disk;
 447         pmem->pgmap.owner = pmem;
 448         pmem->pfn_flags = PFN_DEV;
 449         if (is_nd_pfn(dev)) {
 450                 pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
 451                 addr = devm_memremap_pages(dev, &pmem->pgmap);
 452                 pfn_sb = nd_pfn->pfn_sb;
 453                 pmem->data_offset = le64_to_cpu(pfn_sb->dataoff);
 454                 pmem->pfn_pad = resource_size(res) -
 455                         range_len(&pmem->pgmap.range);
 456                 pmem->pfn_flags |= PFN_MAP;
 457                 bb_range = pmem->pgmap.range;
 458                 bb_range.start += pmem->data_offset;
 459         } else if (pmem_should_map_pages(dev)) {
 460                 pmem->pgmap.range.start = res->start;
 461                 pmem->pgmap.range.end = res->end;
 462                 pmem->pgmap.nr_range = 1;
 463                 pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
 464                 addr = devm_memremap_pages(dev, &pmem->pgmap);
 465                 pmem->pfn_flags |= PFN_MAP;
 466                 bb_range = pmem->pgmap.range;
 467         } else {
 468                 addr = devm_memremap(dev, pmem->phys_addr,
 469                                 pmem->size, ARCH_MEMREMAP_PMEM);
 470                 bb_range.start =  res->start;
 471                 bb_range.end = res->end;
 472         }
 473
 474         if (IS_ERR(addr)) {
 475                 rc = PTR_ERR(addr);
 476                 goto out;
 477         }
 478         pmem->virt_addr = addr;
 479
 480         blk_queue_write_cache(q, true, fua);
 481         blk_queue_physical_block_size(q, PAGE_SIZE);
 482         blk_queue_logical_block_size(q, pmem_sector_size(ndns));
 483         blk_queue_max_hw_sectors(q, UINT_MAX);
 484         blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
 485         if (pmem->pfn_flags & PFN_MAP)
 486                 blk_queue_flag_set(QUEUE_FLAG_DAX, q);
 487
 488         disk->fops              = &pmem_fops;
 489         disk->private_data      = pmem;
 490         nvdimm_namespace_disk_name(ndns, disk->disk_name);
 491         set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset)
 492                         / 512);
 493         if (devm_init_badblocks(dev, &pmem->bb))
 494                 return -ENOMEM;
 495         nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_range);
 496         disk->bb = &pmem->bb;
 497
 498         if (is_nvdimm_sync(nd_region))
 499                 flags = DAXDEV_F_SYNC;
 500         dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops, flags);
 501         if (IS_ERR(dax_dev)) {
 502                 rc = PTR_ERR(dax_dev);
 503                 goto out;
 504         }
 505         dax_write_cache(dax_dev, nvdimm_has_cache(nd_region));
 506         pmem->dax_dev = dax_dev;
 507
 508         rc = device_add_disk(dev, disk, pmem_attribute_groups);
 509         if (rc)
 510                 goto out_cleanup_dax;
 511         if (devm_add_action_or_reset(dev, pmem_release_disk, pmem))
 512                 return -ENOMEM;
 513
 514         nvdimm_check_and_set_ro(disk);
 515
 516         pmem->bb_state = sysfs_get_dirent(disk_to_dev(disk)->kobj.sd,
 517                                           "badblocks");
 518         if (!pmem->bb_state)
 519                 dev_warn(dev, "'badblocks' notification disabled\n");
 520         return 0;
 521
 522 out_cleanup_dax:
 523         kill_dax(pmem->dax_dev);
 524         put_dax(pmem->dax_dev);
 525 out:
 526         blk_cleanup_disk(pmem->disk);
 527         return rc;
 528 }
 529
 530 static int nd_pmem_probe(struct device *dev)
 531 {
 532         int ret;
 533         struct nd_namespace_common *ndns;
 534
 535         ndns = nvdimm_namespace_common_probe(dev);
 536         if (IS_ERR(ndns))
 537                 return PTR_ERR(ndns);
 538
 539         if (is_nd_btt(dev))
 540                 return nvdimm_namespace_attach_btt(ndns);
 541
 542         if (is_nd_pfn(dev))
 543                 return pmem_attach_disk(dev, ndns);
 544
 545         ret = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
 546         if (ret)
 547                 return ret;
 548
 549         ret = nd_btt_probe(dev, ndns);
 550         if (ret == 0)
 551                 return -ENXIO;
 552
 553         /*
 554          * We have two failure conditions here, there is no
 555          * info reserver block or we found a valid info reserve block
 556          * but failed to initialize the pfn superblock.
 557          *
 558          * For the first case consider namespace as a raw pmem namespace
 559          * and attach a disk.
 560          *
 561          * For the latter, consider this a success and advance the namespace
 562          * seed.
 563          */
 564         ret = nd_pfn_probe(dev, ndns);
 565         if (ret == 0)
 566                 return -ENXIO;
 567         else if (ret == -EOPNOTSUPP)
 568                 return ret;
 569
 570         ret = nd_dax_probe(dev, ndns);
 571         if (ret == 0)
 572                 return -ENXIO;
 573         else if (ret == -EOPNOTSUPP)
 574                 return ret;
 575
 576         /* probe complete, attach handles namespace enabling */
 577         devm_namespace_disable(dev, ndns);
 578
 579         return pmem_attach_disk(dev, ndns);
 580 }
 581
 582 static void nd_pmem_remove(struct device *dev)
 583 {
 584         struct pmem_device *pmem = dev_get_drvdata(dev);
 585
 586         if (is_nd_btt(dev))
 587                 nvdimm_namespace_detach_btt(to_nd_btt(dev));
 588         else {
 589                 /*
 590                  * Note, this assumes nd_device_lock() context to not
 591                  * race nd_pmem_notify()
 592                  */
 593                 sysfs_put(pmem->bb_state);
 594                 pmem->bb_state = NULL;
 595         }
 596         nvdimm_flush(to_nd_region(dev->parent), NULL);
 597 }
 598
 599 static void nd_pmem_shutdown(struct device *dev)
 600 {
 601         nvdimm_flush(to_nd_region(dev->parent), NULL);
 602 }
 603
 604 static void pmem_revalidate_poison(struct device *dev)
 605 {
 606         struct nd_region *nd_region;
 607         resource_size_t offset = 0, end_trunc = 0;
 608         struct nd_namespace_common *ndns;
 609         struct nd_namespace_io *nsio;
 610         struct badblocks *bb;
 611         struct range range;
 612         struct kernfs_node *bb_state;
 613
 614         if (is_nd_btt(dev)) {
 615                 struct nd_btt *nd_btt = to_nd_btt(dev);
 616
 617                 ndns = nd_btt->ndns;
 618                 nd_region = to_nd_region(ndns->dev.parent);
 619                 nsio = to_nd_namespace_io(&ndns->dev);
 620                 bb = &nsio->bb;
 621                 bb_state = NULL;
 622         } else {
 623                 struct pmem_device *pmem = dev_get_drvdata(dev);
 624
 625                 nd_region = to_region(pmem);
 626                 bb = &pmem->bb;
 627                 bb_state = pmem->bb_state;
 628
 629                 if (is_nd_pfn(dev)) {
 630                         struct nd_pfn *nd_pfn = to_nd_pfn(dev);
 631                         struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
 632
 633                         ndns = nd_pfn->ndns;
 634                         offset = pmem->data_offset +
 635                                         __le32_to_cpu(pfn_sb->start_pad);
 636                         end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
 637                 } else {
 638                         ndns = to_ndns(dev);
 639                 }
 640
 641                 nsio = to_nd_namespace_io(&ndns->dev);
 642         }
 643
 644         range.start = nsio->res.start + offset;
 645         range.end = nsio->res.end - end_trunc;
 646         nvdimm_badblocks_populate(nd_region, bb, &range);
 647         if (bb_state)
 648                 sysfs_notify_dirent(bb_state);
 649 }
 650
 651 static void pmem_revalidate_region(struct device *dev)
 652 {
 653         struct pmem_device *pmem;
 654
 655         if (is_nd_btt(dev)) {
 656                 struct nd_btt *nd_btt = to_nd_btt(dev);
 657                 struct btt *btt = nd_btt->btt;
 658
 659                 nvdimm_check_and_set_ro(btt->btt_disk);
 660                 return;
 661         }
 662
 663         pmem = dev_get_drvdata(dev);
 664         nvdimm_check_and_set_ro(pmem->disk);
 665 }
 666
 667 static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
 668 {
 669         switch (event) {
 670         case NVDIMM_REVALIDATE_POISON:
 671                 pmem_revalidate_poison(dev);
 672                 break;
 673         case NVDIMM_REVALIDATE_REGION:
 674                 pmem_revalidate_region(dev);
 675                 break;
 676         default:
 677                 dev_WARN_ONCE(dev, 1, "notify: unknown event: %d\n", event);
 678                 break;
 679         }
 680 }
 681
 682 MODULE_ALIAS("pmem");
 683 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
 684 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM);
 685 static struct nd_device_driver nd_pmem_driver = {
 686         .probe = nd_pmem_probe,
 687         .remove = nd_pmem_remove,
 688         .notify = nd_pmem_notify,
 689         .shutdown = nd_pmem_shutdown,
 690         .drv = {
 691                 .name = "nd_pmem",
 692         },
 693         .type = ND_DRIVER_NAMESPACE_IO | ND_DRIVER_NAMESPACE_PMEM,
 694 };
 695
 696 module_nd_driver(nd_pmem_driver);
 697
 698 MODULE_AUTHOR("Ross Zwisler <[email protected]>");
 699 MODULE_LICENSE("GPL v2");