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 <hch@lst.de>.
   7  * Copyright (c) 2015, Boaz Harrosh <boaz@plexistor.com>.
   8  */
   9
  10 #include <linux/blkdev.h>
  11 #include <linux/hdreg.h>
  12 #include <linux/init.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/set_memory.h>
  15 #include <linux/module.h>
  16 #include <linux/moduleparam.h>
  17 #include <linux/badblocks.h>
  18 #include <linux/memremap.h>
  19 #include <linux/vmalloc.h>
  20 #include <linux/blk-mq.h>
  21 #include <linux/pfn_t.h>
  22 #include <linux/slab.h>
  23 #include <linux/uio.h>
  24 #include <linux/dax.h>
  25 #include <linux/nd.h>
  26 #include <linux/mm.h>
  27 #include <asm/cacheflush.h>
  28 #include "pmem.h"
  29 #include "btt.h"
  30 #include "pfn.h"
  31 #include "nd.h"
  32
  33 static struct device *to_dev(struct pmem_device *pmem)
  34 {
  35         /*
  36          * nvdimm bus services need a 'dev' parameter, and we record the device
  37          * at init in bb.dev.
  38          */
  39         return pmem->bb.dev;
  40 }
  41
  42 static struct nd_region *to_region(struct pmem_device *pmem)
  43 {
  44         return to_nd_region(to_dev(pmem)->parent);
  45 }
  46
  47 static void hwpoison_clear(struct pmem_device *pmem,
  48                 phys_addr_t phys, unsigned int len)
  49 {
  50         unsigned long pfn_start, pfn_end, pfn;
  51
  52         /* only pmem in the linear map supports HWPoison */
  53         if (is_vmalloc_addr(pmem->virt_addr))
  54                 return;
  55
  56         pfn_start = PHYS_PFN(phys);
  57         pfn_end = pfn_start + PHYS_PFN(len);
  58         for (pfn = pfn_start; pfn < pfn_end; pfn++) {
  59                 struct page *page = pfn_to_page(pfn);
  60
  61                 /*
  62                  * Note, no need to hold a get_dev_pagemap() reference
  63                  * here since we're in the driver I/O path and
  64                  * outstanding I/O requests pin the dev_pagemap.
  65                  */
  66                 if (test_and_clear_pmem_poison(page))
  67                         clear_mce_nospec(pfn);
  68         }
  69 }
  70
  71 static blk_status_t pmem_clear_poison(struct pmem_device *pmem,
  72                 phys_addr_t offset, unsigned int len)
  73 {
  74         struct device *dev = to_dev(pmem);
  75         sector_t sector;
  76         long cleared;
  77         blk_status_t rc = BLK_STS_OK;
  78
  79         sector = (offset - pmem->data_offset) / 512;
  80
  81         cleared = nvdimm_clear_poison(dev, pmem->phys_addr + offset, len);
  82         if (cleared < len)
  83                 rc = BLK_STS_IOERR;
  84         if (cleared > 0 && cleared / 512) {
  85                 hwpoison_clear(pmem, pmem->phys_addr + offset, cleared);
  86                 cleared /= 512;
  87                 dev_dbg(dev, "%#llx clear %ld sector%s\n",
  88                                 (unsigned long long) sector, cleared,
  89                                 cleared > 1 ? "s" : "");
  90                 badblocks_clear(&pmem->bb, sector, cleared);
  91                 if (pmem->bb_state)
  92                         sysfs_notify_dirent(pmem->bb_state);
  93         }
  94
  95         arch_invalidate_pmem(pmem->virt_addr + offset, len);
  96
  97         return rc;
  98 }
  99
 100 static void write_pmem(void *pmem_addr, struct page *page,
 101                 unsigned int off, unsigned int len)
 102 {
 103         unsigned int chunk;
 104         void *mem;
 105
 106         while (len) {
 107                 mem = kmap_atomic(page);
 108                 chunk = min_t(unsigned int, len, PAGE_SIZE - off);
 109                 memcpy_flushcache(pmem_addr, mem + off, chunk);
 110                 kunmap_atomic(mem);
 111                 len -= chunk;
 112                 off = 0;
 113                 page++;
 114                 pmem_addr += chunk;
 115         }
 116 }
 117
 118 static blk_status_t read_pmem(struct page *page, unsigned int off,
 119                 void *pmem_addr, unsigned int len)
 120 {
 121         unsigned int chunk;
 122         unsigned long rem;
 123         void *mem;
 124
 125         while (len) {
 126                 mem = kmap_atomic(page);
 127                 chunk = min_t(unsigned int, len, PAGE_SIZE - off);
 128                 rem = copy_mc_to_kernel(mem + off, pmem_addr, chunk);
 129                 kunmap_atomic(mem);
 130                 if (rem)
 131                         return BLK_STS_IOERR;
 132                 len -= chunk;
 133                 off = 0;
 134                 page++;
 135                 pmem_addr += chunk;
 136         }
 137         return BLK_STS_OK;
 138 }
 139
 140 static blk_status_t pmem_do_read(struct pmem_device *pmem,
 141                         struct page *page, unsigned int page_off,
 142                         sector_t sector, unsigned int len)
 143 {
 144         blk_status_t rc;
 145         phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
 146         void *pmem_addr = pmem->virt_addr + pmem_off;
 147
 148         if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
 149                 return BLK_STS_IOERR;
 150
 151         rc = read_pmem(page, page_off, pmem_addr, len);
 152         flush_dcache_page(page);
 153         return rc;
 154 }
 155
 156 static blk_status_t pmem_do_write(struct pmem_device *pmem,
 157                         struct page *page, unsigned int page_off,
 158                         sector_t sector, unsigned int len)
 159 {
 160         blk_status_t rc = BLK_STS_OK;
 161         bool bad_pmem = false;
 162         phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
 163         void *pmem_addr = pmem->virt_addr + pmem_off;
 164
 165         if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
 166                 bad_pmem = true;
 167
 168         /*
 169          * Note that we write the data both before and after
 170          * clearing poison.  The write before clear poison
 171          * handles situations where the latest written data is
 172          * preserved and the clear poison operation simply marks
 173          * the address range as valid without changing the data.
 174          * In this case application software can assume that an
 175          * interrupted write will either return the new good
 176          * data or an error.
 177          *
 178          * However, if pmem_clear_poison() leaves the data in an
 179          * indeterminate state we need to perform the write
 180          * after clear poison.
 181          */
 182         flush_dcache_page(page);
 183         write_pmem(pmem_addr, page, page_off, len);
 184         if (unlikely(bad_pmem)) {
 185                 rc = pmem_clear_poison(pmem, pmem_off, len);
 186                 write_pmem(pmem_addr, page, page_off, len);
 187         }
 188
 189         return rc;
 190 }
 191
 192 static blk_qc_t pmem_submit_bio(struct bio *bio)
 193 {
 194         int ret = 0;
 195         blk_status_t rc = 0;
 196         bool do_acct;
 197         unsigned long start;
 198         struct bio_vec bvec;
 199         struct bvec_iter iter;
 200         struct pmem_device *pmem = bio->bi_bdev->bd_disk->private_data;
 201         struct nd_region *nd_region = to_region(pmem);
 202
 203         if (bio->bi_opf & REQ_PREFLUSH)
 204                 ret = nvdimm_flush(nd_region, bio);
 205
 206         do_acct = blk_queue_io_stat(bio->bi_bdev->bd_disk->queue);
 207         if (do_acct)
 208                 start = bio_start_io_acct(bio);
 209         bio_for_each_segment(bvec, bio, iter) {
 210                 if (op_is_write(bio_op(bio)))
 211                         rc = pmem_do_write(pmem, bvec.bv_page, bvec.bv_offset,
 212                                 iter.bi_sector, bvec.bv_len);
 213                 else
 214                         rc = pmem_do_read(pmem, bvec.bv_page, bvec.bv_offset,
 215                                 iter.bi_sector, bvec.bv_len);
 216                 if (rc) {
 217                         bio->bi_status = rc;
 218                         break;
 219                 }
 220         }
 221         if (do_acct)
 222                 bio_end_io_acct(bio, start);
 223
 224         if (bio->bi_opf & REQ_FUA)
 225                 ret = nvdimm_flush(nd_region, bio);
 226
 227         if (ret)
 228                 bio->bi_status = errno_to_blk_status(ret);
 229
 230         bio_endio(bio);
 231         return BLK_QC_T_NONE;
 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 const struct attribute_group *pmem_attribute_groups[] = {
 331         &dax_attribute_group,
 332         NULL,
 333 };
 334
 335 static void pmem_pagemap_cleanup(struct dev_pagemap *pgmap)
 336 {
 337         struct request_queue *q =
 338                 container_of(pgmap->ref, struct request_queue, q_usage_counter);
 339
 340         blk_cleanup_queue(q);
 341 }
 342
 343 static void pmem_release_queue(void *pgmap)
 344 {
 345         pmem_pagemap_cleanup(pgmap);
 346 }
 347
 348 static void pmem_pagemap_kill(struct dev_pagemap *pgmap)
 349 {
 350         struct request_queue *q =
 351                 container_of(pgmap->ref, struct request_queue, q_usage_counter);
 352
 353         blk_freeze_queue_start(q);
 354 }
 355
 356 static void pmem_release_disk(void *__pmem)
 357 {
 358         struct pmem_device *pmem = __pmem;
 359
 360         kill_dax(pmem->dax_dev);
 361         put_dax(pmem->dax_dev);
 362         del_gendisk(pmem->disk);
 363         put_disk(pmem->disk);
 364 }
 365
 366 static const struct dev_pagemap_ops fsdax_pagemap_ops = {
 367         .kill                   = pmem_pagemap_kill,
 368         .cleanup                = pmem_pagemap_cleanup,
 369 };
 370
 371 static int pmem_attach_disk(struct device *dev,
 372                 struct nd_namespace_common *ndns)
 373 {
 374         struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
 375         struct nd_region *nd_region = to_nd_region(dev->parent);
 376         int nid = dev_to_node(dev), fua;
 377         struct resource *res = &nsio->res;
 378         struct range bb_range;
 379         struct nd_pfn *nd_pfn = NULL;
 380         struct dax_device *dax_dev;
 381         struct nd_pfn_sb *pfn_sb;
 382         struct pmem_device *pmem;
 383         struct request_queue *q;
 384         struct device *gendev;
 385         struct gendisk *disk;
 386         void *addr;
 387         int rc;
 388         unsigned long flags = 0UL;
 389
 390         pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
 391         if (!pmem)
 392                 return -ENOMEM;
 393
 394         rc = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
 395         if (rc)
 396                 return rc;
 397
 398         /* while nsio_rw_bytes is active, parse a pfn info block if present */
 399         if (is_nd_pfn(dev)) {
 400                 nd_pfn = to_nd_pfn(dev);
 401                 rc = nvdimm_setup_pfn(nd_pfn, &pmem->pgmap);
 402                 if (rc)
 403                         return rc;
 404         }
 405
 406         /* we're attaching a block device, disable raw namespace access */
 407         devm_namespace_disable(dev, ndns);
 408
 409         dev_set_drvdata(dev, pmem);
 410         pmem->phys_addr = res->start;
 411         pmem->size = resource_size(res);
 412         fua = nvdimm_has_flush(nd_region);
 413         if (!IS_ENABLED(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) || fua < 0) {
 414                 dev_warn(dev, "unable to guarantee persistence of writes\n");
 415                 fua = 0;
 416         }
 417
 418         if (!devm_request_mem_region(dev, res->start, resource_size(res),
 419                                 dev_name(&ndns->dev))) {
 420                 dev_warn(dev, "could not reserve region %pR\n", res);
 421                 return -EBUSY;
 422         }
 423
 424         q = blk_alloc_queue(dev_to_node(dev));
 425         if (!q)
 426                 return -ENOMEM;
 427
 428         pmem->pfn_flags = PFN_DEV;
 429         pmem->pgmap.ref = &q->q_usage_counter;
 430         if (is_nd_pfn(dev)) {
 431                 pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
 432                 pmem->pgmap.ops = &fsdax_pagemap_ops;
 433                 addr = devm_memremap_pages(dev, &pmem->pgmap);
 434                 pfn_sb = nd_pfn->pfn_sb;
 435                 pmem->data_offset = le64_to_cpu(pfn_sb->dataoff);
 436                 pmem->pfn_pad = resource_size(res) -
 437                         range_len(&pmem->pgmap.range);
 438                 pmem->pfn_flags |= PFN_MAP;
 439                 bb_range = pmem->pgmap.range;
 440                 bb_range.start += pmem->data_offset;
 441         } else if (pmem_should_map_pages(dev)) {
 442                 pmem->pgmap.range.start = res->start;
 443                 pmem->pgmap.range.end = res->end;
 444                 pmem->pgmap.nr_range = 1;
 445                 pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
 446                 pmem->pgmap.ops = &fsdax_pagemap_ops;
 447                 addr = devm_memremap_pages(dev, &pmem->pgmap);
 448                 pmem->pfn_flags |= PFN_MAP;
 449                 bb_range = pmem->pgmap.range;
 450         } else {
 451                 if (devm_add_action_or_reset(dev, pmem_release_queue,
 452                                         &pmem->pgmap))
 453                         return -ENOMEM;
 454                 addr = devm_memremap(dev, pmem->phys_addr,
 455                                 pmem->size, ARCH_MEMREMAP_PMEM);
 456                 bb_range.start =  res->start;
 457                 bb_range.end = res->end;
 458         }
 459
 460         if (IS_ERR(addr))
 461                 return PTR_ERR(addr);
 462         pmem->virt_addr = addr;
 463
 464         blk_queue_write_cache(q, true, fua);
 465         blk_queue_physical_block_size(q, PAGE_SIZE);
 466         blk_queue_logical_block_size(q, pmem_sector_size(ndns));
 467         blk_queue_max_hw_sectors(q, UINT_MAX);
 468         blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
 469         if (pmem->pfn_flags & PFN_MAP)
 470                 blk_queue_flag_set(QUEUE_FLAG_DAX, q);
 471
 472         disk = alloc_disk_node(0, nid);
 473         if (!disk)
 474                 return -ENOMEM;
 475         pmem->disk = disk;
 476
 477         disk->fops              = &pmem_fops;
 478         disk->queue             = q;
 479         disk->flags             = GENHD_FL_EXT_DEVT;
 480         disk->private_data      = pmem;
 481         nvdimm_namespace_disk_name(ndns, disk->disk_name);
 482         set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset)
 483                         / 512);
 484         if (devm_init_badblocks(dev, &pmem->bb))
 485                 return -ENOMEM;
 486         nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_range);
 487         disk->bb = &pmem->bb;
 488
 489         if (is_nvdimm_sync(nd_region))
 490                 flags = DAXDEV_F_SYNC;
 491         dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops, flags);
 492         if (IS_ERR(dax_dev)) {
 493                 put_disk(disk);
 494                 return PTR_ERR(dax_dev);
 495         }
 496         dax_write_cache(dax_dev, nvdimm_has_cache(nd_region));
 497         pmem->dax_dev = dax_dev;
 498         gendev = disk_to_dev(disk);
 499         gendev->groups = pmem_attribute_groups;
 500
 501         device_add_disk(dev, disk, NULL);
 502         if (devm_add_action_or_reset(dev, pmem_release_disk, pmem))
 503                 return -ENOMEM;
 504
 505         nvdimm_check_and_set_ro(disk);
 506
 507         pmem->bb_state = sysfs_get_dirent(disk_to_dev(disk)->kobj.sd,
 508                                           "badblocks");
 509         if (!pmem->bb_state)
 510                 dev_warn(dev, "'badblocks' notification disabled\n");
 511
 512         return 0;
 513 }
 514
 515 static int nd_pmem_probe(struct device *dev)
 516 {
 517         int ret;
 518         struct nd_namespace_common *ndns;
 519
 520         ndns = nvdimm_namespace_common_probe(dev);
 521         if (IS_ERR(ndns))
 522                 return PTR_ERR(ndns);
 523
 524         if (is_nd_btt(dev))
 525                 return nvdimm_namespace_attach_btt(ndns);
 526
 527         if (is_nd_pfn(dev))
 528                 return pmem_attach_disk(dev, ndns);
 529
 530         ret = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
 531         if (ret)
 532                 return ret;
 533
 534         ret = nd_btt_probe(dev, ndns);
 535         if (ret == 0)
 536                 return -ENXIO;
 537
 538         /*
 539          * We have two failure conditions here, there is no
 540          * info reserver block or we found a valid info reserve block
 541          * but failed to initialize the pfn superblock.
 542          *
 543          * For the first case consider namespace as a raw pmem namespace
 544          * and attach a disk.
 545          *
 546          * For the latter, consider this a success and advance the namespace
 547          * seed.
 548          */
 549         ret = nd_pfn_probe(dev, ndns);
 550         if (ret == 0)
 551                 return -ENXIO;
 552         else if (ret == -EOPNOTSUPP)
 553                 return ret;
 554
 555         ret = nd_dax_probe(dev, ndns);
 556         if (ret == 0)
 557                 return -ENXIO;
 558         else if (ret == -EOPNOTSUPP)
 559                 return ret;
 560
 561         /* probe complete, attach handles namespace enabling */
 562         devm_namespace_disable(dev, ndns);
 563
 564         return pmem_attach_disk(dev, ndns);
 565 }
 566
 567 static void nd_pmem_remove(struct device *dev)
 568 {
 569         struct pmem_device *pmem = dev_get_drvdata(dev);
 570
 571         if (is_nd_btt(dev))
 572                 nvdimm_namespace_detach_btt(to_nd_btt(dev));
 573         else {
 574                 /*
 575                  * Note, this assumes nd_device_lock() context to not
 576                  * race nd_pmem_notify()
 577                  */
 578                 sysfs_put(pmem->bb_state);
 579                 pmem->bb_state = NULL;
 580         }
 581         nvdimm_flush(to_nd_region(dev->parent), NULL);
 582 }
 583
 584 static void nd_pmem_shutdown(struct device *dev)
 585 {
 586         nvdimm_flush(to_nd_region(dev->parent), NULL);
 587 }
 588
 589 static void pmem_revalidate_poison(struct device *dev)
 590 {
 591         struct nd_region *nd_region;
 592         resource_size_t offset = 0, end_trunc = 0;
 593         struct nd_namespace_common *ndns;
 594         struct nd_namespace_io *nsio;
 595         struct badblocks *bb;
 596         struct range range;
 597         struct kernfs_node *bb_state;
 598
 599         if (is_nd_btt(dev)) {
 600                 struct nd_btt *nd_btt = to_nd_btt(dev);
 601
 602                 ndns = nd_btt->ndns;
 603                 nd_region = to_nd_region(ndns->dev.parent);
 604                 nsio = to_nd_namespace_io(&ndns->dev);
 605                 bb = &nsio->bb;
 606                 bb_state = NULL;
 607         } else {
 608                 struct pmem_device *pmem = dev_get_drvdata(dev);
 609
 610                 nd_region = to_region(pmem);
 611                 bb = &pmem->bb;
 612                 bb_state = pmem->bb_state;
 613
 614                 if (is_nd_pfn(dev)) {
 615                         struct nd_pfn *nd_pfn = to_nd_pfn(dev);
 616                         struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
 617
 618                         ndns = nd_pfn->ndns;
 619                         offset = pmem->data_offset +
 620                                         __le32_to_cpu(pfn_sb->start_pad);
 621                         end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
 622                 } else {
 623                         ndns = to_ndns(dev);
 624                 }
 625
 626                 nsio = to_nd_namespace_io(&ndns->dev);
 627         }
 628
 629         range.start = nsio->res.start + offset;
 630         range.end = nsio->res.end - end_trunc;
 631         nvdimm_badblocks_populate(nd_region, bb, &range);
 632         if (bb_state)
 633                 sysfs_notify_dirent(bb_state);
 634 }
 635
 636 static void pmem_revalidate_region(struct device *dev)
 637 {
 638         struct pmem_device *pmem;
 639
 640         if (is_nd_btt(dev)) {
 641                 struct nd_btt *nd_btt = to_nd_btt(dev);
 642                 struct btt *btt = nd_btt->btt;
 643
 644                 nvdimm_check_and_set_ro(btt->btt_disk);
 645                 return;
 646         }
 647
 648         pmem = dev_get_drvdata(dev);
 649         nvdimm_check_and_set_ro(pmem->disk);
 650 }
 651
 652 static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
 653 {
 654         switch (event) {
 655         case NVDIMM_REVALIDATE_POISON:
 656                 pmem_revalidate_poison(dev);
 657                 break;
 658         case NVDIMM_REVALIDATE_REGION:
 659                 pmem_revalidate_region(dev);
 660                 break;
 661         default:
 662                 dev_WARN_ONCE(dev, 1, "notify: unknown event: %d\n", event);
 663                 break;
 664         }
 665 }
 666
 667 MODULE_ALIAS("pmem");
 668 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
 669 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM);
 670 static struct nd_device_driver nd_pmem_driver = {
 671         .probe = nd_pmem_probe,
 672         .remove = nd_pmem_remove,
 673         .notify = nd_pmem_notify,
 674         .shutdown = nd_pmem_shutdown,
 675         .drv = {
 676                 .name = "nd_pmem",
 677         },
 678         .type = ND_DRIVER_NAMESPACE_IO | ND_DRIVER_NAMESPACE_PMEM,
 679 };
 680
 681 module_nd_driver(nd_pmem_driver);
 682
 683 MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
 684 MODULE_LICENSE("GPL v2");