Merge branch 'for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
[linux-2.6-microblaze.git] / 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 "pfn.h"
30 #include "nd.h"
31
32 static struct device *to_dev(struct pmem_device *pmem)
33 {
34         /*
35          * nvdimm bus services need a 'dev' parameter, and we record the device
36          * at init in bb.dev.
37          */
38         return pmem->bb.dev;
39 }
40
41 static struct nd_region *to_region(struct pmem_device *pmem)
42 {
43         return to_nd_region(to_dev(pmem)->parent);
44 }
45
46 static void hwpoison_clear(struct pmem_device *pmem,
47                 phys_addr_t phys, unsigned int len)
48 {
49         unsigned long pfn_start, pfn_end, pfn;
50
51         /* only pmem in the linear map supports HWPoison */
52         if (is_vmalloc_addr(pmem->virt_addr))
53                 return;
54
55         pfn_start = PHYS_PFN(phys);
56         pfn_end = pfn_start + PHYS_PFN(len);
57         for (pfn = pfn_start; pfn < pfn_end; pfn++) {
58                 struct page *page = pfn_to_page(pfn);
59
60                 /*
61                  * Note, no need to hold a get_dev_pagemap() reference
62                  * here since we're in the driver I/O path and
63                  * outstanding I/O requests pin the dev_pagemap.
64                  */
65                 if (test_and_clear_pmem_poison(page))
66                         clear_mce_nospec(pfn);
67         }
68 }
69
70 static blk_status_t pmem_clear_poison(struct pmem_device *pmem,
71                 phys_addr_t offset, unsigned int len)
72 {
73         struct device *dev = to_dev(pmem);
74         sector_t sector;
75         long cleared;
76         blk_status_t rc = BLK_STS_OK;
77
78         sector = (offset - pmem->data_offset) / 512;
79
80         cleared = nvdimm_clear_poison(dev, pmem->phys_addr + offset, len);
81         if (cleared < len)
82                 rc = BLK_STS_IOERR;
83         if (cleared > 0 && cleared / 512) {
84                 hwpoison_clear(pmem, pmem->phys_addr + offset, cleared);
85                 cleared /= 512;
86                 dev_dbg(dev, "%#llx clear %ld sector%s\n",
87                                 (unsigned long long) sector, cleared,
88                                 cleared > 1 ? "s" : "");
89                 badblocks_clear(&pmem->bb, sector, cleared);
90                 if (pmem->bb_state)
91                         sysfs_notify_dirent(pmem->bb_state);
92         }
93
94         arch_invalidate_pmem(pmem->virt_addr + offset, len);
95
96         return rc;
97 }
98
99 static void write_pmem(void *pmem_addr, struct page *page,
100                 unsigned int off, unsigned int len)
101 {
102         unsigned int chunk;
103         void *mem;
104
105         while (len) {
106                 mem = kmap_atomic(page);
107                 chunk = min_t(unsigned int, len, PAGE_SIZE - off);
108                 memcpy_flushcache(pmem_addr, mem + off, chunk);
109                 kunmap_atomic(mem);
110                 len -= chunk;
111                 off = 0;
112                 page++;
113                 pmem_addr += chunk;
114         }
115 }
116
117 static blk_status_t read_pmem(struct page *page, unsigned int off,
118                 void *pmem_addr, unsigned int len)
119 {
120         unsigned int chunk;
121         unsigned long rem;
122         void *mem;
123
124         while (len) {
125                 mem = kmap_atomic(page);
126                 chunk = min_t(unsigned int, len, PAGE_SIZE - off);
127                 rem = copy_mc_to_kernel(mem + off, pmem_addr, chunk);
128                 kunmap_atomic(mem);
129                 if (rem)
130                         return BLK_STS_IOERR;
131                 len -= chunk;
132                 off = 0;
133                 page++;
134                 pmem_addr += chunk;
135         }
136         return BLK_STS_OK;
137 }
138
139 static blk_status_t pmem_do_read(struct pmem_device *pmem,
140                         struct page *page, unsigned int page_off,
141                         sector_t sector, unsigned int len)
142 {
143         blk_status_t rc;
144         phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
145         void *pmem_addr = pmem->virt_addr + pmem_off;
146
147         if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
148                 return BLK_STS_IOERR;
149
150         rc = read_pmem(page, page_off, pmem_addr, len);
151         flush_dcache_page(page);
152         return rc;
153 }
154
155 static blk_status_t pmem_do_write(struct pmem_device *pmem,
156                         struct page *page, unsigned int page_off,
157                         sector_t sector, unsigned int len)
158 {
159         blk_status_t rc = BLK_STS_OK;
160         bool bad_pmem = false;
161         phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
162         void *pmem_addr = pmem->virt_addr + pmem_off;
163
164         if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
165                 bad_pmem = true;
166
167         /*
168          * Note that we write the data both before and after
169          * clearing poison.  The write before clear poison
170          * handles situations where the latest written data is
171          * preserved and the clear poison operation simply marks
172          * the address range as valid without changing the data.
173          * In this case application software can assume that an
174          * interrupted write will either return the new good
175          * data or an error.
176          *
177          * However, if pmem_clear_poison() leaves the data in an
178          * indeterminate state we need to perform the write
179          * after clear poison.
180          */
181         flush_dcache_page(page);
182         write_pmem(pmem_addr, page, page_off, len);
183         if (unlikely(bad_pmem)) {
184                 rc = pmem_clear_poison(pmem, pmem_off, len);
185                 write_pmem(pmem_addr, page, page_off, len);
186         }
187
188         return rc;
189 }
190
191 static blk_qc_t pmem_submit_bio(struct bio *bio)
192 {
193         int ret = 0;
194         blk_status_t rc = 0;
195         bool do_acct;
196         unsigned long start;
197         struct bio_vec bvec;
198         struct bvec_iter iter;
199         struct pmem_device *pmem = bio->bi_bdev->bd_disk->private_data;
200         struct nd_region *nd_region = to_region(pmem);
201
202         if (bio->bi_opf & REQ_PREFLUSH)
203                 ret = nvdimm_flush(nd_region, bio);
204
205         do_acct = blk_queue_io_stat(bio->bi_bdev->bd_disk->queue);
206         if (do_acct)
207                 start = bio_start_io_acct(bio);
208         bio_for_each_segment(bvec, bio, iter) {
209                 if (op_is_write(bio_op(bio)))
210                         rc = pmem_do_write(pmem, bvec.bv_page, bvec.bv_offset,
211                                 iter.bi_sector, bvec.bv_len);
212                 else
213                         rc = pmem_do_read(pmem, bvec.bv_page, bvec.bv_offset,
214                                 iter.bi_sector, bvec.bv_len);
215                 if (rc) {
216                         bio->bi_status = rc;
217                         break;
218                 }
219         }
220         if (do_acct)
221                 bio_end_io_acct(bio, start);
222
223         if (bio->bi_opf & REQ_FUA)
224                 ret = nvdimm_flush(nd_region, bio);
225
226         if (ret)
227                 bio->bi_status = errno_to_blk_status(ret);
228
229         bio_endio(bio);
230         return BLK_QC_T_NONE;
231 }
232
233 static int pmem_rw_page(struct block_device *bdev, sector_t sector,
234                        struct page *page, unsigned int op)
235 {
236         struct pmem_device *pmem = bdev->bd_disk->private_data;
237         blk_status_t rc;
238
239         if (op_is_write(op))
240                 rc = pmem_do_write(pmem, page, 0, sector, thp_size(page));
241         else
242                 rc = pmem_do_read(pmem, page, 0, sector, thp_size(page));
243         /*
244          * The ->rw_page interface is subtle and tricky.  The core
245          * retries on any error, so we can only invoke page_endio() in
246          * the successful completion case.  Otherwise, we'll see crashes
247          * caused by double completion.
248          */
249         if (rc == 0)
250                 page_endio(page, op_is_write(op), 0);
251
252         return blk_status_to_errno(rc);
253 }
254
255 /* see "strong" declaration in tools/testing/nvdimm/pmem-dax.c */
256 __weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
257                 long nr_pages, void **kaddr, pfn_t *pfn)
258 {
259         resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
260
261         if (unlikely(is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) / 512,
262                                         PFN_PHYS(nr_pages))))
263                 return -EIO;
264
265         if (kaddr)
266                 *kaddr = pmem->virt_addr + offset;
267         if (pfn)
268                 *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
269
270         /*
271          * If badblocks are present, limit known good range to the
272          * requested range.
273          */
274         if (unlikely(pmem->bb.count))
275                 return nr_pages;
276         return PHYS_PFN(pmem->size - pmem->pfn_pad - offset);
277 }
278
279 static const struct block_device_operations pmem_fops = {
280         .owner =                THIS_MODULE,
281         .submit_bio =           pmem_submit_bio,
282         .rw_page =              pmem_rw_page,
283 };
284
285 static int pmem_dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
286                                     size_t nr_pages)
287 {
288         struct pmem_device *pmem = dax_get_private(dax_dev);
289
290         return blk_status_to_errno(pmem_do_write(pmem, ZERO_PAGE(0), 0,
291                                    PFN_PHYS(pgoff) >> SECTOR_SHIFT,
292                                    PAGE_SIZE));
293 }
294
295 static long pmem_dax_direct_access(struct dax_device *dax_dev,
296                 pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn)
297 {
298         struct pmem_device *pmem = dax_get_private(dax_dev);
299
300         return __pmem_direct_access(pmem, pgoff, nr_pages, kaddr, pfn);
301 }
302
303 /*
304  * Use the 'no check' versions of copy_from_iter_flushcache() and
305  * copy_mc_to_iter() to bypass HARDENED_USERCOPY overhead. Bounds
306  * checking, both file offset and device offset, is handled by
307  * dax_iomap_actor()
308  */
309 static size_t pmem_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff,
310                 void *addr, size_t bytes, struct iov_iter *i)
311 {
312         return _copy_from_iter_flushcache(addr, bytes, i);
313 }
314
315 static size_t pmem_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff,
316                 void *addr, size_t bytes, struct iov_iter *i)
317 {
318         return _copy_mc_to_iter(addr, bytes, i);
319 }
320
321 static const struct dax_operations pmem_dax_ops = {
322         .direct_access = pmem_dax_direct_access,
323         .dax_supported = generic_fsdax_supported,
324         .copy_from_iter = pmem_copy_from_iter,
325         .copy_to_iter = pmem_copy_to_iter,
326         .zero_page_range = pmem_dax_zero_page_range,
327 };
328
329 static const struct attribute_group *pmem_attribute_groups[] = {
330         &dax_attribute_group,
331         NULL,
332 };
333
334 static void pmem_pagemap_cleanup(struct dev_pagemap *pgmap)
335 {
336         struct request_queue *q =
337                 container_of(pgmap->ref, struct request_queue, q_usage_counter);
338
339         blk_cleanup_queue(q);
340 }
341
342 static void pmem_release_queue(void *pgmap)
343 {
344         pmem_pagemap_cleanup(pgmap);
345 }
346
347 static void pmem_pagemap_kill(struct dev_pagemap *pgmap)
348 {
349         struct request_queue *q =
350                 container_of(pgmap->ref, struct request_queue, q_usage_counter);
351
352         blk_freeze_queue_start(q);
353 }
354
355 static void pmem_release_disk(void *__pmem)
356 {
357         struct pmem_device *pmem = __pmem;
358
359         kill_dax(pmem->dax_dev);
360         put_dax(pmem->dax_dev);
361         del_gendisk(pmem->disk);
362         put_disk(pmem->disk);
363 }
364
365 static const struct dev_pagemap_ops fsdax_pagemap_ops = {
366         .kill                   = pmem_pagemap_kill,
367         .cleanup                = pmem_pagemap_cleanup,
368 };
369
370 static int pmem_attach_disk(struct device *dev,
371                 struct nd_namespace_common *ndns)
372 {
373         struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
374         struct nd_region *nd_region = to_nd_region(dev->parent);
375         int nid = dev_to_node(dev), fua;
376         struct resource *res = &nsio->res;
377         struct range bb_range;
378         struct nd_pfn *nd_pfn = NULL;
379         struct dax_device *dax_dev;
380         struct nd_pfn_sb *pfn_sb;
381         struct pmem_device *pmem;
382         struct request_queue *q;
383         struct device *gendev;
384         struct gendisk *disk;
385         void *addr;
386         int rc;
387         unsigned long flags = 0UL;
388
389         pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
390         if (!pmem)
391                 return -ENOMEM;
392
393         rc = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
394         if (rc)
395                 return rc;
396
397         /* while nsio_rw_bytes is active, parse a pfn info block if present */
398         if (is_nd_pfn(dev)) {
399                 nd_pfn = to_nd_pfn(dev);
400                 rc = nvdimm_setup_pfn(nd_pfn, &pmem->pgmap);
401                 if (rc)
402                         return rc;
403         }
404
405         /* we're attaching a block device, disable raw namespace access */
406         devm_namespace_disable(dev, ndns);
407
408         dev_set_drvdata(dev, pmem);
409         pmem->phys_addr = res->start;
410         pmem->size = resource_size(res);
411         fua = nvdimm_has_flush(nd_region);
412         if (!IS_ENABLED(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) || fua < 0) {
413                 dev_warn(dev, "unable to guarantee persistence of writes\n");
414                 fua = 0;
415         }
416
417         if (!devm_request_mem_region(dev, res->start, resource_size(res),
418                                 dev_name(&ndns->dev))) {
419                 dev_warn(dev, "could not reserve region %pR\n", res);
420                 return -EBUSY;
421         }
422
423         q = blk_alloc_queue(dev_to_node(dev));
424         if (!q)
425                 return -ENOMEM;
426
427         pmem->pfn_flags = PFN_DEV;
428         pmem->pgmap.ref = &q->q_usage_counter;
429         if (is_nd_pfn(dev)) {
430                 pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
431                 pmem->pgmap.ops = &fsdax_pagemap_ops;
432                 addr = devm_memremap_pages(dev, &pmem->pgmap);
433                 pfn_sb = nd_pfn->pfn_sb;
434                 pmem->data_offset = le64_to_cpu(pfn_sb->dataoff);
435                 pmem->pfn_pad = resource_size(res) -
436                         range_len(&pmem->pgmap.range);
437                 pmem->pfn_flags |= PFN_MAP;
438                 bb_range = pmem->pgmap.range;
439                 bb_range.start += pmem->data_offset;
440         } else if (pmem_should_map_pages(dev)) {
441                 pmem->pgmap.range.start = res->start;
442                 pmem->pgmap.range.end = res->end;
443                 pmem->pgmap.nr_range = 1;
444                 pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
445                 pmem->pgmap.ops = &fsdax_pagemap_ops;
446                 addr = devm_memremap_pages(dev, &pmem->pgmap);
447                 pmem->pfn_flags |= PFN_MAP;
448                 bb_range = pmem->pgmap.range;
449         } else {
450                 if (devm_add_action_or_reset(dev, pmem_release_queue,
451                                         &pmem->pgmap))
452                         return -ENOMEM;
453                 addr = devm_memremap(dev, pmem->phys_addr,
454                                 pmem->size, ARCH_MEMREMAP_PMEM);
455                 bb_range.start =  res->start;
456                 bb_range.end = res->end;
457         }
458
459         if (IS_ERR(addr))
460                 return PTR_ERR(addr);
461         pmem->virt_addr = addr;
462
463         blk_queue_write_cache(q, true, fua);
464         blk_queue_physical_block_size(q, PAGE_SIZE);
465         blk_queue_logical_block_size(q, pmem_sector_size(ndns));
466         blk_queue_max_hw_sectors(q, UINT_MAX);
467         blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
468         if (pmem->pfn_flags & PFN_MAP)
469                 blk_queue_flag_set(QUEUE_FLAG_DAX, q);
470
471         disk = alloc_disk_node(0, nid);
472         if (!disk)
473                 return -ENOMEM;
474         pmem->disk = disk;
475
476         disk->fops              = &pmem_fops;
477         disk->queue             = q;
478         disk->flags             = GENHD_FL_EXT_DEVT;
479         disk->private_data      = pmem;
480         nvdimm_namespace_disk_name(ndns, disk->disk_name);
481         set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset)
482                         / 512);
483         if (devm_init_badblocks(dev, &pmem->bb))
484                 return -ENOMEM;
485         nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_range);
486         disk->bb = &pmem->bb;
487
488         if (is_nvdimm_sync(nd_region))
489                 flags = DAXDEV_F_SYNC;
490         dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops, flags);
491         if (IS_ERR(dax_dev)) {
492                 put_disk(disk);
493                 return PTR_ERR(dax_dev);
494         }
495         dax_write_cache(dax_dev, nvdimm_has_cache(nd_region));
496         pmem->dax_dev = dax_dev;
497         gendev = disk_to_dev(disk);
498         gendev->groups = pmem_attribute_groups;
499
500         device_add_disk(dev, disk, NULL);
501         if (devm_add_action_or_reset(dev, pmem_release_disk, pmem))
502                 return -ENOMEM;
503
504         nvdimm_check_and_set_ro(disk);
505
506         pmem->bb_state = sysfs_get_dirent(disk_to_dev(disk)->kobj.sd,
507                                           "badblocks");
508         if (!pmem->bb_state)
509                 dev_warn(dev, "'badblocks' notification disabled\n");
510
511         return 0;
512 }
513
514 static int nd_pmem_probe(struct device *dev)
515 {
516         int ret;
517         struct nd_namespace_common *ndns;
518
519         ndns = nvdimm_namespace_common_probe(dev);
520         if (IS_ERR(ndns))
521                 return PTR_ERR(ndns);
522
523         if (is_nd_btt(dev))
524                 return nvdimm_namespace_attach_btt(ndns);
525
526         if (is_nd_pfn(dev))
527                 return pmem_attach_disk(dev, ndns);
528
529         ret = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
530         if (ret)
531                 return ret;
532
533         ret = nd_btt_probe(dev, ndns);
534         if (ret == 0)
535                 return -ENXIO;
536
537         /*
538          * We have two failure conditions here, there is no
539          * info reserver block or we found a valid info reserve block
540          * but failed to initialize the pfn superblock.
541          *
542          * For the first case consider namespace as a raw pmem namespace
543          * and attach a disk.
544          *
545          * For the latter, consider this a success and advance the namespace
546          * seed.
547          */
548         ret = nd_pfn_probe(dev, ndns);
549         if (ret == 0)
550                 return -ENXIO;
551         else if (ret == -EOPNOTSUPP)
552                 return ret;
553
554         ret = nd_dax_probe(dev, ndns);
555         if (ret == 0)
556                 return -ENXIO;
557         else if (ret == -EOPNOTSUPP)
558                 return ret;
559
560         /* probe complete, attach handles namespace enabling */
561         devm_namespace_disable(dev, ndns);
562
563         return pmem_attach_disk(dev, ndns);
564 }
565
566 static int nd_pmem_remove(struct device *dev)
567 {
568         struct pmem_device *pmem = dev_get_drvdata(dev);
569
570         if (is_nd_btt(dev))
571                 nvdimm_namespace_detach_btt(to_nd_btt(dev));
572         else {
573                 /*
574                  * Note, this assumes nd_device_lock() context to not
575                  * race nd_pmem_notify()
576                  */
577                 sysfs_put(pmem->bb_state);
578                 pmem->bb_state = NULL;
579         }
580         nvdimm_flush(to_nd_region(dev->parent), NULL);
581
582         return 0;
583 }
584
585 static void nd_pmem_shutdown(struct device *dev)
586 {
587         nvdimm_flush(to_nd_region(dev->parent), NULL);
588 }
589
590 static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
591 {
592         struct nd_region *nd_region;
593         resource_size_t offset = 0, end_trunc = 0;
594         struct nd_namespace_common *ndns;
595         struct nd_namespace_io *nsio;
596         struct badblocks *bb;
597         struct range range;
598         struct kernfs_node *bb_state;
599
600         if (event != NVDIMM_REVALIDATE_POISON)
601                 return;
602
603         if (is_nd_btt(dev)) {
604                 struct nd_btt *nd_btt = to_nd_btt(dev);
605
606                 ndns = nd_btt->ndns;
607                 nd_region = to_nd_region(ndns->dev.parent);
608                 nsio = to_nd_namespace_io(&ndns->dev);
609                 bb = &nsio->bb;
610                 bb_state = NULL;
611         } else {
612                 struct pmem_device *pmem = dev_get_drvdata(dev);
613
614                 nd_region = to_region(pmem);
615                 bb = &pmem->bb;
616                 bb_state = pmem->bb_state;
617
618                 if (is_nd_pfn(dev)) {
619                         struct nd_pfn *nd_pfn = to_nd_pfn(dev);
620                         struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
621
622                         ndns = nd_pfn->ndns;
623                         offset = pmem->data_offset +
624                                         __le32_to_cpu(pfn_sb->start_pad);
625                         end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
626                 } else {
627                         ndns = to_ndns(dev);
628                 }
629
630                 nsio = to_nd_namespace_io(&ndns->dev);
631         }
632
633         range.start = nsio->res.start + offset;
634         range.end = nsio->res.end - end_trunc;
635         nvdimm_badblocks_populate(nd_region, bb, &range);
636         if (bb_state)
637                 sysfs_notify_dirent(bb_state);
638 }
639
640 MODULE_ALIAS("pmem");
641 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
642 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM);
643 static struct nd_device_driver nd_pmem_driver = {
644         .probe = nd_pmem_probe,
645         .remove = nd_pmem_remove,
646         .notify = nd_pmem_notify,
647         .shutdown = nd_pmem_shutdown,
648         .drv = {
649                 .name = "nd_pmem",
650         },
651         .type = ND_DRIVER_NAMESPACE_IO | ND_DRIVER_NAMESPACE_PMEM,
652 };
653
654 module_nd_driver(nd_pmem_driver);
655
656 MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
657 MODULE_LICENSE("GPL v2");