xref: /openbmc/linux/drivers/nvdimm/pmem.c (revision dbf563ee)
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/backing-dev.h>
27 #include <linux/mm.h>
28 #include <asm/cacheflush.h>
29 #include "pmem.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 = memcpy_mcsafe(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_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_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 	.revalidate_disk =	nvdimm_revalidate_disk,
285 };
286 
287 static int pmem_dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
288 				    size_t nr_pages)
289 {
290 	struct pmem_device *pmem = dax_get_private(dax_dev);
291 
292 	return blk_status_to_errno(pmem_do_write(pmem, ZERO_PAGE(0), 0,
293 				   PFN_PHYS(pgoff) >> SECTOR_SHIFT,
294 				   PAGE_SIZE));
295 }
296 
297 static long pmem_dax_direct_access(struct dax_device *dax_dev,
298 		pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn)
299 {
300 	struct pmem_device *pmem = dax_get_private(dax_dev);
301 
302 	return __pmem_direct_access(pmem, pgoff, nr_pages, kaddr, pfn);
303 }
304 
305 /*
306  * Use the 'no check' versions of copy_from_iter_flushcache() and
307  * copy_to_iter_mcsafe() to bypass HARDENED_USERCOPY overhead. Bounds
308  * checking, both file offset and device offset, is handled by
309  * dax_iomap_actor()
310  */
311 static size_t pmem_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff,
312 		void *addr, size_t bytes, struct iov_iter *i)
313 {
314 	return _copy_from_iter_flushcache(addr, bytes, i);
315 }
316 
317 static size_t pmem_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff,
318 		void *addr, size_t bytes, struct iov_iter *i)
319 {
320 	return _copy_to_iter_mcsafe(addr, bytes, i);
321 }
322 
323 static const struct dax_operations pmem_dax_ops = {
324 	.direct_access = pmem_dax_direct_access,
325 	.dax_supported = generic_fsdax_supported,
326 	.copy_from_iter = pmem_copy_from_iter,
327 	.copy_to_iter = pmem_copy_to_iter,
328 	.zero_page_range = pmem_dax_zero_page_range,
329 };
330 
331 static const struct attribute_group *pmem_attribute_groups[] = {
332 	&dax_attribute_group,
333 	NULL,
334 };
335 
336 static void pmem_pagemap_cleanup(struct dev_pagemap *pgmap)
337 {
338 	struct request_queue *q =
339 		container_of(pgmap->ref, struct request_queue, q_usage_counter);
340 
341 	blk_cleanup_queue(q);
342 }
343 
344 static void pmem_release_queue(void *pgmap)
345 {
346 	pmem_pagemap_cleanup(pgmap);
347 }
348 
349 static void pmem_pagemap_kill(struct dev_pagemap *pgmap)
350 {
351 	struct request_queue *q =
352 		container_of(pgmap->ref, struct request_queue, q_usage_counter);
353 
354 	blk_freeze_queue_start(q);
355 }
356 
357 static void pmem_release_disk(void *__pmem)
358 {
359 	struct pmem_device *pmem = __pmem;
360 
361 	kill_dax(pmem->dax_dev);
362 	put_dax(pmem->dax_dev);
363 	del_gendisk(pmem->disk);
364 	put_disk(pmem->disk);
365 }
366 
367 static const struct dev_pagemap_ops fsdax_pagemap_ops = {
368 	.kill			= pmem_pagemap_kill,
369 	.cleanup		= pmem_pagemap_cleanup,
370 };
371 
372 static int pmem_attach_disk(struct device *dev,
373 		struct nd_namespace_common *ndns)
374 {
375 	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
376 	struct nd_region *nd_region = to_nd_region(dev->parent);
377 	int nid = dev_to_node(dev), fua;
378 	struct resource *res = &nsio->res;
379 	struct resource bb_res;
380 	struct nd_pfn *nd_pfn = NULL;
381 	struct dax_device *dax_dev;
382 	struct nd_pfn_sb *pfn_sb;
383 	struct pmem_device *pmem;
384 	struct request_queue *q;
385 	struct device *gendev;
386 	struct gendisk *disk;
387 	void *addr;
388 	int rc;
389 	unsigned long flags = 0UL;
390 
391 	pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
392 	if (!pmem)
393 		return -ENOMEM;
394 
395 	rc = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
396 	if (rc)
397 		return rc;
398 
399 	/* while nsio_rw_bytes is active, parse a pfn info block if present */
400 	if (is_nd_pfn(dev)) {
401 		nd_pfn = to_nd_pfn(dev);
402 		rc = nvdimm_setup_pfn(nd_pfn, &pmem->pgmap);
403 		if (rc)
404 			return rc;
405 	}
406 
407 	/* we're attaching a block device, disable raw namespace access */
408 	devm_namespace_disable(dev, ndns);
409 
410 	dev_set_drvdata(dev, pmem);
411 	pmem->phys_addr = res->start;
412 	pmem->size = resource_size(res);
413 	fua = nvdimm_has_flush(nd_region);
414 	if (!IS_ENABLED(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) || fua < 0) {
415 		dev_warn(dev, "unable to guarantee persistence of writes\n");
416 		fua = 0;
417 	}
418 
419 	if (!devm_request_mem_region(dev, res->start, resource_size(res),
420 				dev_name(&ndns->dev))) {
421 		dev_warn(dev, "could not reserve region %pR\n", res);
422 		return -EBUSY;
423 	}
424 
425 	q = blk_alloc_queue(dev_to_node(dev));
426 	if (!q)
427 		return -ENOMEM;
428 
429 	pmem->pfn_flags = PFN_DEV;
430 	pmem->pgmap.ref = &q->q_usage_counter;
431 	if (is_nd_pfn(dev)) {
432 		pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
433 		pmem->pgmap.ops = &fsdax_pagemap_ops;
434 		addr = devm_memremap_pages(dev, &pmem->pgmap);
435 		pfn_sb = nd_pfn->pfn_sb;
436 		pmem->data_offset = le64_to_cpu(pfn_sb->dataoff);
437 		pmem->pfn_pad = resource_size(res) -
438 			resource_size(&pmem->pgmap.res);
439 		pmem->pfn_flags |= PFN_MAP;
440 		memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res));
441 		bb_res.start += pmem->data_offset;
442 	} else if (pmem_should_map_pages(dev)) {
443 		memcpy(&pmem->pgmap.res, &nsio->res, sizeof(pmem->pgmap.res));
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 		memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res));
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 		memcpy(&bb_res, &nsio->res, sizeof(bb_res));
456 	}
457 
458 	if (IS_ERR(addr))
459 		return PTR_ERR(addr);
460 	pmem->virt_addr = addr;
461 
462 	blk_queue_write_cache(q, true, fua);
463 	blk_queue_physical_block_size(q, PAGE_SIZE);
464 	blk_queue_logical_block_size(q, pmem_sector_size(ndns));
465 	blk_queue_max_hw_sectors(q, UINT_MAX);
466 	blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
467 	if (pmem->pfn_flags & PFN_MAP)
468 		blk_queue_flag_set(QUEUE_FLAG_DAX, q);
469 
470 	disk = alloc_disk_node(0, nid);
471 	if (!disk)
472 		return -ENOMEM;
473 	pmem->disk = disk;
474 
475 	disk->fops		= &pmem_fops;
476 	disk->queue		= q;
477 	disk->flags		= GENHD_FL_EXT_DEVT;
478 	disk->private_data	= pmem;
479 	disk->queue->backing_dev_info->capabilities |= BDI_CAP_SYNCHRONOUS_IO;
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_res);
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 	revalidate_disk(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 resource res;
597 	struct badblocks *bb;
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 	res.start = nsio->res.start + offset;
634 	res.end = nsio->res.end - end_trunc;
635 	nvdimm_badblocks_populate(nd_region, bb, &res);
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");
658