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v6.13.7
  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/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/kstrtox.h>
 21#include <linux/vmalloc.h>
 22#include <linux/blk-mq.h>
 23#include <linux/pfn_t.h>
 24#include <linux/slab.h>
 25#include <linux/uio.h>
 26#include <linux/dax.h>
 27#include <linux/nd.h>
 28#include <linux/mm.h>
 29#include <asm/cacheflush.h>
 30#include "pmem.h"
 31#include "btt.h"
 32#include "pfn.h"
 33#include "nd.h"
 
 34
 35static struct device *to_dev(struct pmem_device *pmem)
 36{
 37	/*
 38	 * nvdimm bus services need a 'dev' parameter, and we record the device
 39	 * at init in bb.dev.
 40	 */
 41	return pmem->bb.dev;
 42}
 43
 44static struct nd_region *to_region(struct pmem_device *pmem)
 45{
 46	return to_nd_region(to_dev(pmem)->parent);
 47}
 48
 49static phys_addr_t pmem_to_phys(struct pmem_device *pmem, phys_addr_t offset)
 50{
 51	return pmem->phys_addr + offset;
 52}
 53
 54static sector_t to_sect(struct pmem_device *pmem, phys_addr_t offset)
 55{
 56	return (offset - pmem->data_offset) >> SECTOR_SHIFT;
 57}
 58
 59static phys_addr_t to_offset(struct pmem_device *pmem, sector_t sector)
 60{
 61	return (sector << SECTOR_SHIFT) + pmem->data_offset;
 62}
 63
 64static void pmem_mkpage_present(struct pmem_device *pmem, phys_addr_t offset,
 65		unsigned int len)
 66{
 67	phys_addr_t phys = pmem_to_phys(pmem, offset);
 68	unsigned long pfn_start, pfn_end, pfn;
 69
 70	/* only pmem in the linear map supports HWPoison */
 71	if (is_vmalloc_addr(pmem->virt_addr))
 72		return;
 73
 74	pfn_start = PHYS_PFN(phys);
 75	pfn_end = pfn_start + PHYS_PFN(len);
 76	for (pfn = pfn_start; pfn < pfn_end; pfn++) {
 77		struct page *page = pfn_to_page(pfn);
 78
 79		/*
 80		 * Note, no need to hold a get_dev_pagemap() reference
 81		 * here since we're in the driver I/O path and
 82		 * outstanding I/O requests pin the dev_pagemap.
 83		 */
 84		if (test_and_clear_pmem_poison(page))
 85			clear_mce_nospec(pfn);
 86	}
 87}
 88
 89static void pmem_clear_bb(struct pmem_device *pmem, sector_t sector, long blks)
 90{
 91	if (blks == 0)
 92		return;
 93	badblocks_clear(&pmem->bb, sector, blks);
 94	if (pmem->bb_state)
 95		sysfs_notify_dirent(pmem->bb_state);
 96}
 97
 98static long __pmem_clear_poison(struct pmem_device *pmem,
 99		phys_addr_t offset, unsigned int len)
100{
101	phys_addr_t phys = pmem_to_phys(pmem, offset);
102	long cleared = nvdimm_clear_poison(to_dev(pmem), phys, len);
103
104	if (cleared > 0) {
105		pmem_mkpage_present(pmem, offset, cleared);
106		arch_invalidate_pmem(pmem->virt_addr + offset, len);
107	}
108	return cleared;
109}
110
111static blk_status_t pmem_clear_poison(struct pmem_device *pmem,
112		phys_addr_t offset, unsigned int len)
113{
114	long cleared = __pmem_clear_poison(pmem, offset, len);
 
 
 
115
116	if (cleared < 0)
117		return BLK_STS_IOERR;
118
119	pmem_clear_bb(pmem, to_sect(pmem, offset), cleared >> SECTOR_SHIFT);
120	if (cleared < len)
121		return BLK_STS_IOERR;
122	return BLK_STS_OK;
 
 
 
 
 
 
 
 
 
 
 
 
 
123}
124
125static void write_pmem(void *pmem_addr, struct page *page,
126		unsigned int off, unsigned int len)
127{
128	unsigned int chunk;
129	void *mem;
130
131	while (len) {
132		mem = kmap_atomic(page);
133		chunk = min_t(unsigned int, len, PAGE_SIZE - off);
134		memcpy_flushcache(pmem_addr, mem + off, chunk);
135		kunmap_atomic(mem);
136		len -= chunk;
137		off = 0;
138		page++;
139		pmem_addr += chunk;
140	}
141}
142
143static blk_status_t read_pmem(struct page *page, unsigned int off,
144		void *pmem_addr, unsigned int len)
145{
146	unsigned int chunk;
147	unsigned long rem;
148	void *mem;
149
150	while (len) {
151		mem = kmap_atomic(page);
152		chunk = min_t(unsigned int, len, PAGE_SIZE - off);
153		rem = copy_mc_to_kernel(mem + off, pmem_addr, chunk);
154		kunmap_atomic(mem);
155		if (rem)
156			return BLK_STS_IOERR;
157		len -= chunk;
158		off = 0;
159		page++;
160		pmem_addr += chunk;
161	}
162	return BLK_STS_OK;
163}
164
165static blk_status_t pmem_do_read(struct pmem_device *pmem,
166			struct page *page, unsigned int page_off,
167			sector_t sector, unsigned int len)
168{
169	blk_status_t rc;
170	phys_addr_t pmem_off = to_offset(pmem, sector);
 
171	void *pmem_addr = pmem->virt_addr + pmem_off;
172
173	if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
174		return BLK_STS_IOERR;
175
176	rc = read_pmem(page, page_off, pmem_addr, len);
177	flush_dcache_page(page);
178	return rc;
179}
180
181static blk_status_t pmem_do_write(struct pmem_device *pmem,
182			struct page *page, unsigned int page_off,
183			sector_t sector, unsigned int len)
184{
185	phys_addr_t pmem_off = to_offset(pmem, sector);
186	void *pmem_addr = pmem->virt_addr + pmem_off;
187
188	if (unlikely(is_bad_pmem(&pmem->bb, sector, len))) {
189		blk_status_t rc = pmem_clear_poison(pmem, pmem_off, len);
190
191		if (rc != BLK_STS_OK)
192			return rc;
 
 
 
 
 
 
 
 
 
 
 
193	}
194
195	flush_dcache_page(page);
196	write_pmem(pmem_addr, page, page_off, len);
197
198	return BLK_STS_OK;
199}
200
201static void pmem_submit_bio(struct bio *bio)
202{
203	int ret = 0;
204	blk_status_t rc = 0;
205	bool do_acct;
206	unsigned long start;
207	struct bio_vec bvec;
208	struct bvec_iter iter;
209	struct pmem_device *pmem = bio->bi_bdev->bd_disk->private_data;
210	struct nd_region *nd_region = to_region(pmem);
211
212	if (bio->bi_opf & REQ_PREFLUSH)
213		ret = nvdimm_flush(nd_region, bio);
214
215	do_acct = blk_queue_io_stat(bio->bi_bdev->bd_disk->queue);
216	if (do_acct)
217		start = bio_start_io_acct(bio);
218	bio_for_each_segment(bvec, bio, iter) {
219		if (op_is_write(bio_op(bio)))
220			rc = pmem_do_write(pmem, bvec.bv_page, bvec.bv_offset,
221				iter.bi_sector, bvec.bv_len);
222		else
223			rc = pmem_do_read(pmem, bvec.bv_page, bvec.bv_offset,
224				iter.bi_sector, bvec.bv_len);
225		if (rc) {
226			bio->bi_status = rc;
227			break;
228		}
229	}
230	if (do_acct)
231		bio_end_io_acct(bio, start);
232
233	if (bio->bi_opf & REQ_FUA)
234		ret = nvdimm_flush(nd_region, bio);
235
236	if (ret)
237		bio->bi_status = errno_to_blk_status(ret);
238
239	bio_endio(bio);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
240}
241
242/* see "strong" declaration in tools/testing/nvdimm/pmem-dax.c */
243__weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
244		long nr_pages, enum dax_access_mode mode, void **kaddr,
245		pfn_t *pfn)
246{
247	resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
248	sector_t sector = PFN_PHYS(pgoff) >> SECTOR_SHIFT;
249	unsigned int num = PFN_PHYS(nr_pages) >> SECTOR_SHIFT;
250	struct badblocks *bb = &pmem->bb;
251	sector_t first_bad;
252	int num_bad;
253
254	if (kaddr)
255		*kaddr = pmem->virt_addr + offset;
256	if (pfn)
257		*pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
258
259	if (bb->count &&
260	    badblocks_check(bb, sector, num, &first_bad, &num_bad)) {
261		long actual_nr;
262
263		if (mode != DAX_RECOVERY_WRITE)
264			return -EHWPOISON;
265
266		/*
267		 * Set the recovery stride is set to kernel page size because
268		 * the underlying driver and firmware clear poison functions
269		 * don't appear to handle large chunk(such as 2MiB) reliably.
270		 */
271		actual_nr = PHYS_PFN(
272			PAGE_ALIGN((first_bad - sector) << SECTOR_SHIFT));
273		dev_dbg(pmem->bb.dev, "start sector(%llu), nr_pages(%ld), first_bad(%llu), actual_nr(%ld)\n",
274				sector, nr_pages, first_bad, actual_nr);
275		if (actual_nr)
276			return actual_nr;
277		return 1;
278	}
279
280	/*
281	 * If badblocks are present but not in the range, limit known good range
282	 * to the requested range.
283	 */
284	if (bb->count)
285		return nr_pages;
286	return PHYS_PFN(pmem->size - pmem->pfn_pad - offset);
287}
288
289static const struct block_device_operations pmem_fops = {
290	.owner =		THIS_MODULE,
291	.submit_bio =		pmem_submit_bio,
 
292};
293
294static int pmem_dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
295				    size_t nr_pages)
296{
297	struct pmem_device *pmem = dax_get_private(dax_dev);
298
299	return blk_status_to_errno(pmem_do_write(pmem, ZERO_PAGE(0), 0,
300				   PFN_PHYS(pgoff) >> SECTOR_SHIFT,
301				   PAGE_SIZE));
302}
303
304static long pmem_dax_direct_access(struct dax_device *dax_dev,
305		pgoff_t pgoff, long nr_pages, enum dax_access_mode mode,
306		void **kaddr, pfn_t *pfn)
307{
308	struct pmem_device *pmem = dax_get_private(dax_dev);
309
310	return __pmem_direct_access(pmem, pgoff, nr_pages, mode, kaddr, pfn);
311}
312
313/*
314 * The recovery write thread started out as a normal pwrite thread and
315 * when the filesystem was told about potential media error in the
316 * range, filesystem turns the normal pwrite to a dax_recovery_write.
317 *
318 * The recovery write consists of clearing media poison, clearing page
319 * HWPoison bit, re-enable page-wide read-write permission, flush the
320 * caches and finally write.  A competing pread thread will be held
321 * off during the recovery process since data read back might not be
322 * valid, and this is achieved by clearing the badblock records after
323 * the recovery write is complete. Competing recovery write threads
324 * are already serialized by writer lock held by dax_iomap_rw().
325 */
326static size_t pmem_recovery_write(struct dax_device *dax_dev, pgoff_t pgoff,
327		void *addr, size_t bytes, struct iov_iter *i)
328{
329	struct pmem_device *pmem = dax_get_private(dax_dev);
330	size_t olen, len, off;
331	phys_addr_t pmem_off;
332	struct device *dev = pmem->bb.dev;
333	long cleared;
334
335	off = offset_in_page(addr);
336	len = PFN_PHYS(PFN_UP(off + bytes));
337	if (!is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) >> SECTOR_SHIFT, len))
338		return _copy_from_iter_flushcache(addr, bytes, i);
339
340	/*
341	 * Not page-aligned range cannot be recovered. This should not
342	 * happen unless something else went wrong.
343	 */
344	if (off || !PAGE_ALIGNED(bytes)) {
345		dev_dbg(dev, "Found poison, but addr(%p) or bytes(%#zx) not page aligned\n",
346			addr, bytes);
347		return 0;
348	}
349
350	pmem_off = PFN_PHYS(pgoff) + pmem->data_offset;
351	cleared = __pmem_clear_poison(pmem, pmem_off, len);
352	if (cleared > 0 && cleared < len) {
353		dev_dbg(dev, "poison cleared only %ld out of %zu bytes\n",
354			cleared, len);
355		return 0;
356	}
357	if (cleared < 0) {
358		dev_dbg(dev, "poison clear failed: %ld\n", cleared);
359		return 0;
360	}
361
362	olen = _copy_from_iter_flushcache(addr, bytes, i);
363	pmem_clear_bb(pmem, to_sect(pmem, pmem_off), cleared >> SECTOR_SHIFT);
364
365	return olen;
 
 
 
366}
367
368static const struct dax_operations pmem_dax_ops = {
369	.direct_access = pmem_dax_direct_access,
370	.zero_page_range = pmem_dax_zero_page_range,
371	.recovery_write = pmem_recovery_write,
 
372};
373
374static ssize_t write_cache_show(struct device *dev,
375		struct device_attribute *attr, char *buf)
376{
377	struct pmem_device *pmem = dev_to_disk(dev)->private_data;
378
379	return sprintf(buf, "%d\n", !!dax_write_cache_enabled(pmem->dax_dev));
380}
381
382static ssize_t write_cache_store(struct device *dev,
383		struct device_attribute *attr, const char *buf, size_t len)
384{
385	struct pmem_device *pmem = dev_to_disk(dev)->private_data;
386	bool write_cache;
387	int rc;
388
389	rc = kstrtobool(buf, &write_cache);
390	if (rc)
391		return rc;
392	dax_write_cache(pmem->dax_dev, write_cache);
393	return len;
394}
395static DEVICE_ATTR_RW(write_cache);
396
397static umode_t dax_visible(struct kobject *kobj, struct attribute *a, int n)
398{
399#ifndef CONFIG_ARCH_HAS_PMEM_API
400	if (a == &dev_attr_write_cache.attr)
401		return 0;
402#endif
403	return a->mode;
404}
405
406static struct attribute *dax_attributes[] = {
407	&dev_attr_write_cache.attr,
408	NULL,
409};
410
411static const struct attribute_group dax_attribute_group = {
412	.name		= "dax",
413	.attrs		= dax_attributes,
414	.is_visible	= dax_visible,
415};
416
417static const struct attribute_group *pmem_attribute_groups[] = {
418	&dax_attribute_group,
419	NULL,
420};
421
422static void pmem_release_disk(void *__pmem)
423{
424	struct pmem_device *pmem = __pmem;
425
426	dax_remove_host(pmem->disk);
427	kill_dax(pmem->dax_dev);
428	put_dax(pmem->dax_dev);
429	del_gendisk(pmem->disk);
430
431	put_disk(pmem->disk);
432}
433
434static int pmem_pagemap_memory_failure(struct dev_pagemap *pgmap,
435		unsigned long pfn, unsigned long nr_pages, int mf_flags)
436{
437	struct pmem_device *pmem =
438			container_of(pgmap, struct pmem_device, pgmap);
439	u64 offset = PFN_PHYS(pfn) - pmem->phys_addr - pmem->data_offset;
440	u64 len = nr_pages << PAGE_SHIFT;
441
442	return dax_holder_notify_failure(pmem->dax_dev, offset, len, mf_flags);
443}
444
445static const struct dev_pagemap_ops fsdax_pagemap_ops = {
446	.memory_failure		= pmem_pagemap_memory_failure,
 
 
447};
448
449static int pmem_attach_disk(struct device *dev,
450		struct nd_namespace_common *ndns)
451{
452	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
453	struct nd_region *nd_region = to_nd_region(dev->parent);
454	struct queue_limits lim = {
455		.logical_block_size	= pmem_sector_size(ndns),
456		.physical_block_size	= PAGE_SIZE,
457		.max_hw_sectors		= UINT_MAX,
458		.features		= BLK_FEAT_WRITE_CACHE |
459					  BLK_FEAT_SYNCHRONOUS,
460	};
461	int nid = dev_to_node(dev), fua;
462	struct resource *res = &nsio->res;
463	struct range bb_range;
464	struct nd_pfn *nd_pfn = NULL;
465	struct dax_device *dax_dev;
466	struct nd_pfn_sb *pfn_sb;
467	struct pmem_device *pmem;
 
 
468	struct gendisk *disk;
469	void *addr;
470	int rc;
 
471
472	pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
473	if (!pmem)
474		return -ENOMEM;
475
476	rc = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
477	if (rc)
478		return rc;
479
480	/* while nsio_rw_bytes is active, parse a pfn info block if present */
481	if (is_nd_pfn(dev)) {
482		nd_pfn = to_nd_pfn(dev);
483		rc = nvdimm_setup_pfn(nd_pfn, &pmem->pgmap);
484		if (rc)
485			return rc;
486	}
487
488	/* we're attaching a block device, disable raw namespace access */
489	devm_namespace_disable(dev, ndns);
490
491	dev_set_drvdata(dev, pmem);
492	pmem->phys_addr = res->start;
493	pmem->size = resource_size(res);
494	fua = nvdimm_has_flush(nd_region);
495	if (!IS_ENABLED(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) || fua < 0) {
496		dev_warn(dev, "unable to guarantee persistence of writes\n");
497		fua = 0;
498	}
499	if (fua)
500		lim.features |= BLK_FEAT_FUA;
501	if (is_nd_pfn(dev) || pmem_should_map_pages(dev))
502		lim.features |= BLK_FEAT_DAX;
503
504	if (!devm_request_mem_region(dev, res->start, resource_size(res),
505				dev_name(&ndns->dev))) {
506		dev_warn(dev, "could not reserve region %pR\n", res);
507		return -EBUSY;
508	}
509
510	disk = blk_alloc_disk(&lim, nid);
511	if (IS_ERR(disk))
512		return PTR_ERR(disk);
513
514	pmem->disk = disk;
515	pmem->pgmap.owner = pmem;
516	pmem->pfn_flags = PFN_DEV;
 
517	if (is_nd_pfn(dev)) {
518		pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
519		pmem->pgmap.ops = &fsdax_pagemap_ops;
520		addr = devm_memremap_pages(dev, &pmem->pgmap);
521		pfn_sb = nd_pfn->pfn_sb;
522		pmem->data_offset = le64_to_cpu(pfn_sb->dataoff);
523		pmem->pfn_pad = resource_size(res) -
524			range_len(&pmem->pgmap.range);
525		pmem->pfn_flags |= PFN_MAP;
526		bb_range = pmem->pgmap.range;
527		bb_range.start += pmem->data_offset;
528	} else if (pmem_should_map_pages(dev)) {
529		pmem->pgmap.range.start = res->start;
530		pmem->pgmap.range.end = res->end;
531		pmem->pgmap.nr_range = 1;
532		pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
533		pmem->pgmap.ops = &fsdax_pagemap_ops;
534		addr = devm_memremap_pages(dev, &pmem->pgmap);
535		pmem->pfn_flags |= PFN_MAP;
536		bb_range = pmem->pgmap.range;
537	} else {
 
 
 
538		addr = devm_memremap(dev, pmem->phys_addr,
539				pmem->size, ARCH_MEMREMAP_PMEM);
540		bb_range.start =  res->start;
541		bb_range.end = res->end;
542	}
543
544	if (IS_ERR(addr)) {
545		rc = PTR_ERR(addr);
546		goto out;
547	}
548	pmem->virt_addr = addr;
549
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
550	disk->fops		= &pmem_fops;
551	disk->private_data	= pmem;
 
 
552	nvdimm_namespace_disk_name(ndns, disk->disk_name);
553	set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset)
554			/ 512);
555	if (devm_init_badblocks(dev, &pmem->bb))
556		return -ENOMEM;
557	nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_range);
558	disk->bb = &pmem->bb;
559
560	dax_dev = alloc_dax(pmem, &pmem_dax_ops);
561	if (IS_ERR(dax_dev)) {
562		rc = PTR_ERR(dax_dev);
563		if (rc != -EOPNOTSUPP)
564			goto out;
565	} else {
566		set_dax_nocache(dax_dev);
567		set_dax_nomc(dax_dev);
568		if (is_nvdimm_sync(nd_region))
569			set_dax_synchronous(dax_dev);
570		pmem->dax_dev = dax_dev;
571		rc = dax_add_host(dax_dev, disk);
572		if (rc)
573			goto out_cleanup_dax;
574		dax_write_cache(dax_dev, nvdimm_has_cache(nd_region));
575	}
576	rc = device_add_disk(dev, disk, pmem_attribute_groups);
577	if (rc)
578		goto out_remove_host;
 
 
 
579	if (devm_add_action_or_reset(dev, pmem_release_disk, pmem))
580		return -ENOMEM;
581
582	nvdimm_check_and_set_ro(disk);
583
584	pmem->bb_state = sysfs_get_dirent(disk_to_dev(disk)->kobj.sd,
585					  "badblocks");
586	if (!pmem->bb_state)
587		dev_warn(dev, "'badblocks' notification disabled\n");
588	return 0;
589
590out_remove_host:
591	dax_remove_host(pmem->disk);
592out_cleanup_dax:
593	kill_dax(pmem->dax_dev);
594	put_dax(pmem->dax_dev);
595out:
596	put_disk(pmem->disk);
597	return rc;
598}
599
600static int nd_pmem_probe(struct device *dev)
601{
602	int ret;
603	struct nd_namespace_common *ndns;
604
605	ndns = nvdimm_namespace_common_probe(dev);
606	if (IS_ERR(ndns))
607		return PTR_ERR(ndns);
608
 
 
 
609	if (is_nd_btt(dev))
610		return nvdimm_namespace_attach_btt(ndns);
611
612	if (is_nd_pfn(dev))
613		return pmem_attach_disk(dev, ndns);
614
615	ret = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
616	if (ret)
617		return ret;
618
619	ret = nd_btt_probe(dev, ndns);
620	if (ret == 0)
621		return -ENXIO;
622
623	/*
624	 * We have two failure conditions here, there is no
625	 * info reserver block or we found a valid info reserve block
626	 * but failed to initialize the pfn superblock.
627	 *
628	 * For the first case consider namespace as a raw pmem namespace
629	 * and attach a disk.
630	 *
631	 * For the latter, consider this a success and advance the namespace
632	 * seed.
633	 */
634	ret = nd_pfn_probe(dev, ndns);
635	if (ret == 0)
636		return -ENXIO;
637	else if (ret == -EOPNOTSUPP)
638		return ret;
639
640	ret = nd_dax_probe(dev, ndns);
641	if (ret == 0)
642		return -ENXIO;
643	else if (ret == -EOPNOTSUPP)
644		return ret;
645
646	/* probe complete, attach handles namespace enabling */
647	devm_namespace_disable(dev, ndns);
648
649	return pmem_attach_disk(dev, ndns);
650}
651
652static void nd_pmem_remove(struct device *dev)
653{
654	struct pmem_device *pmem = dev_get_drvdata(dev);
655
656	if (is_nd_btt(dev))
657		nvdimm_namespace_detach_btt(to_nd_btt(dev));
658	else {
659		/*
660		 * Note, this assumes device_lock() context to not
661		 * race nd_pmem_notify()
662		 */
663		sysfs_put(pmem->bb_state);
664		pmem->bb_state = NULL;
665	}
666	nvdimm_flush(to_nd_region(dev->parent), NULL);
 
 
667}
668
669static void nd_pmem_shutdown(struct device *dev)
670{
671	nvdimm_flush(to_nd_region(dev->parent), NULL);
672}
673
674static void pmem_revalidate_poison(struct device *dev)
675{
676	struct nd_region *nd_region;
677	resource_size_t offset = 0, end_trunc = 0;
678	struct nd_namespace_common *ndns;
679	struct nd_namespace_io *nsio;
 
680	struct badblocks *bb;
681	struct range range;
682	struct kernfs_node *bb_state;
683
 
 
 
684	if (is_nd_btt(dev)) {
685		struct nd_btt *nd_btt = to_nd_btt(dev);
686
687		ndns = nd_btt->ndns;
688		nd_region = to_nd_region(ndns->dev.parent);
689		nsio = to_nd_namespace_io(&ndns->dev);
690		bb = &nsio->bb;
691		bb_state = NULL;
692	} else {
693		struct pmem_device *pmem = dev_get_drvdata(dev);
694
695		nd_region = to_region(pmem);
696		bb = &pmem->bb;
697		bb_state = pmem->bb_state;
698
699		if (is_nd_pfn(dev)) {
700			struct nd_pfn *nd_pfn = to_nd_pfn(dev);
701			struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
702
703			ndns = nd_pfn->ndns;
704			offset = pmem->data_offset +
705					__le32_to_cpu(pfn_sb->start_pad);
706			end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
707		} else {
708			ndns = to_ndns(dev);
709		}
710
711		nsio = to_nd_namespace_io(&ndns->dev);
712	}
713
714	range.start = nsio->res.start + offset;
715	range.end = nsio->res.end - end_trunc;
716	nvdimm_badblocks_populate(nd_region, bb, &range);
717	if (bb_state)
718		sysfs_notify_dirent(bb_state);
719}
720
721static void pmem_revalidate_region(struct device *dev)
722{
723	struct pmem_device *pmem;
724
725	if (is_nd_btt(dev)) {
726		struct nd_btt *nd_btt = to_nd_btt(dev);
727		struct btt *btt = nd_btt->btt;
728
729		nvdimm_check_and_set_ro(btt->btt_disk);
730		return;
731	}
732
733	pmem = dev_get_drvdata(dev);
734	nvdimm_check_and_set_ro(pmem->disk);
735}
736
737static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
738{
739	switch (event) {
740	case NVDIMM_REVALIDATE_POISON:
741		pmem_revalidate_poison(dev);
742		break;
743	case NVDIMM_REVALIDATE_REGION:
744		pmem_revalidate_region(dev);
745		break;
746	default:
747		dev_WARN_ONCE(dev, 1, "notify: unknown event: %d\n", event);
748		break;
749	}
750}
751
752MODULE_ALIAS("pmem");
753MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
754MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM);
755static struct nd_device_driver nd_pmem_driver = {
756	.probe = nd_pmem_probe,
757	.remove = nd_pmem_remove,
758	.notify = nd_pmem_notify,
759	.shutdown = nd_pmem_shutdown,
760	.drv = {
761		.name = "nd_pmem",
762	},
763	.type = ND_DRIVER_NAMESPACE_IO | ND_DRIVER_NAMESPACE_PMEM,
764};
765
766module_nd_driver(nd_pmem_driver);
767
768MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
769MODULE_DESCRIPTION("NVDIMM Persistent Memory Driver");
770MODULE_LICENSE("GPL v2");
v5.4
  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 <asm/cacheflush.h>
 11#include <linux/blkdev.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/backing-dev.h>
 
 28#include "pmem.h"
 
 29#include "pfn.h"
 30#include "nd.h"
 31#include "nd-core.h"
 32
 33static 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
 42static struct nd_region *to_region(struct pmem_device *pmem)
 43{
 44	return to_nd_region(to_dev(pmem)->parent);
 45}
 46
 47static 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 71static 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
100static 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
118static 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
140static blk_status_t pmem_do_bvec(struct pmem_device *pmem, struct page *page,
141			unsigned int len, unsigned int off, unsigned int op,
142			sector_t sector)
143{
144	blk_status_t rc = BLK_STS_OK;
145	bool bad_pmem = false;
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		bad_pmem = true;
151
152	if (!op_is_write(op)) {
153		if (unlikely(bad_pmem))
154			rc = BLK_STS_IOERR;
155		else {
156			rc = read_pmem(page, off, pmem_addr, len);
157			flush_dcache_page(page);
158		}
159	} else {
160		/*
161		 * Note that we write the data both before and after
162		 * clearing poison.  The write before clear poison
163		 * handles situations where the latest written data is
164		 * preserved and the clear poison operation simply marks
165		 * the address range as valid without changing the data.
166		 * In this case application software can assume that an
167		 * interrupted write will either return the new good
168		 * data or an error.
169		 *
170		 * However, if pmem_clear_poison() leaves the data in an
171		 * indeterminate state we need to perform the write
172		 * after clear poison.
173		 */
174		flush_dcache_page(page);
175		write_pmem(pmem_addr, page, off, len);
176		if (unlikely(bad_pmem)) {
177			rc = pmem_clear_poison(pmem, pmem_off, len);
178			write_pmem(pmem_addr, page, off, len);
179		}
180	}
181
182	return rc;
 
 
 
183}
184
185static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio)
186{
187	int ret = 0;
188	blk_status_t rc = 0;
189	bool do_acct;
190	unsigned long start;
191	struct bio_vec bvec;
192	struct bvec_iter iter;
193	struct pmem_device *pmem = q->queuedata;
194	struct nd_region *nd_region = to_region(pmem);
195
196	if (bio->bi_opf & REQ_PREFLUSH)
197		ret = nvdimm_flush(nd_region, bio);
198
199	do_acct = nd_iostat_start(bio, &start);
 
 
200	bio_for_each_segment(bvec, bio, iter) {
201		rc = pmem_do_bvec(pmem, bvec.bv_page, bvec.bv_len,
202				bvec.bv_offset, bio_op(bio), iter.bi_sector);
 
 
 
 
203		if (rc) {
204			bio->bi_status = rc;
205			break;
206		}
207	}
208	if (do_acct)
209		nd_iostat_end(bio, start);
210
211	if (bio->bi_opf & REQ_FUA)
212		ret = nvdimm_flush(nd_region, bio);
213
214	if (ret)
215		bio->bi_status = errno_to_blk_status(ret);
216
217	bio_endio(bio);
218	return BLK_QC_T_NONE;
219}
220
221static int pmem_rw_page(struct block_device *bdev, sector_t sector,
222		       struct page *page, unsigned int op)
223{
224	struct pmem_device *pmem = bdev->bd_queue->queuedata;
225	blk_status_t rc;
226
227	rc = pmem_do_bvec(pmem, page, hpage_nr_pages(page) * PAGE_SIZE,
228			  0, op, sector);
229
230	/*
231	 * The ->rw_page interface is subtle and tricky.  The core
232	 * retries on any error, so we can only invoke page_endio() in
233	 * the successful completion case.  Otherwise, we'll see crashes
234	 * caused by double completion.
235	 */
236	if (rc == 0)
237		page_endio(page, op_is_write(op), 0);
238
239	return blk_status_to_errno(rc);
240}
241
242/* see "strong" declaration in tools/testing/nvdimm/pmem-dax.c */
243__weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
244		long nr_pages, void **kaddr, pfn_t *pfn)
 
245{
246	resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
247
248	if (unlikely(is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) / 512,
249					PFN_PHYS(nr_pages))))
250		return -EIO;
 
251
252	if (kaddr)
253		*kaddr = pmem->virt_addr + offset;
254	if (pfn)
255		*pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
256
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
257	/*
258	 * If badblocks are present, limit known good range to the
259	 * requested range.
260	 */
261	if (unlikely(pmem->bb.count))
262		return nr_pages;
263	return PHYS_PFN(pmem->size - pmem->pfn_pad - offset);
264}
265
266static const struct block_device_operations pmem_fops = {
267	.owner =		THIS_MODULE,
268	.rw_page =		pmem_rw_page,
269	.revalidate_disk =	nvdimm_revalidate_disk,
270};
271
 
 
 
 
 
 
 
 
 
 
272static long pmem_dax_direct_access(struct dax_device *dax_dev,
273		pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn)
 
274{
275	struct pmem_device *pmem = dax_get_private(dax_dev);
276
277	return __pmem_direct_access(pmem, pgoff, nr_pages, kaddr, pfn);
278}
279
280/*
281 * Use the 'no check' versions of copy_from_iter_flushcache() and
282 * copy_to_iter_mcsafe() to bypass HARDENED_USERCOPY overhead. Bounds
283 * checking, both file offset and device offset, is handled by
284 * dax_iomap_actor()
 
 
 
 
 
 
 
285 */
286static size_t pmem_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff,
287		void *addr, size_t bytes, struct iov_iter *i)
288{
289	return _copy_from_iter_flushcache(addr, bytes, i);
290}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
291
292static size_t pmem_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff,
293		void *addr, size_t bytes, struct iov_iter *i)
294{
295	return _copy_to_iter_mcsafe(addr, bytes, i);
296}
297
298static const struct dax_operations pmem_dax_ops = {
299	.direct_access = pmem_dax_direct_access,
300	.dax_supported = generic_fsdax_supported,
301	.copy_from_iter = pmem_copy_from_iter,
302	.copy_to_iter = pmem_copy_to_iter,
303};
304
305static const struct attribute_group *pmem_attribute_groups[] = {
306	&dax_attribute_group,
307	NULL,
308};
 
 
 
309
310static void pmem_pagemap_cleanup(struct dev_pagemap *pgmap)
 
311{
312	struct request_queue *q =
313		container_of(pgmap->ref, struct request_queue, q_usage_counter);
 
314
315	blk_cleanup_queue(q);
 
 
 
 
316}
 
317
318static void pmem_release_queue(void *pgmap)
319{
320	pmem_pagemap_cleanup(pgmap);
 
 
 
 
321}
322
323static void pmem_pagemap_kill(struct dev_pagemap *pgmap)
324{
325	struct request_queue *q =
326		container_of(pgmap->ref, struct request_queue, q_usage_counter);
 
 
 
 
 
 
327
328	blk_freeze_queue_start(q);
329}
 
 
330
331static void pmem_release_disk(void *__pmem)
332{
333	struct pmem_device *pmem = __pmem;
334
 
335	kill_dax(pmem->dax_dev);
336	put_dax(pmem->dax_dev);
337	del_gendisk(pmem->disk);
 
338	put_disk(pmem->disk);
339}
340
341static void pmem_pagemap_page_free(struct page *page)
 
342{
343	wake_up_var(&page->_refcount);
 
 
 
 
 
344}
345
346static const struct dev_pagemap_ops fsdax_pagemap_ops = {
347	.page_free		= pmem_pagemap_page_free,
348	.kill			= pmem_pagemap_kill,
349	.cleanup		= pmem_pagemap_cleanup,
350};
351
352static int pmem_attach_disk(struct device *dev,
353		struct nd_namespace_common *ndns)
354{
355	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
356	struct nd_region *nd_region = to_nd_region(dev->parent);
 
 
 
 
 
 
 
357	int nid = dev_to_node(dev), fua;
358	struct resource *res = &nsio->res;
359	struct resource bb_res;
360	struct nd_pfn *nd_pfn = NULL;
361	struct dax_device *dax_dev;
362	struct nd_pfn_sb *pfn_sb;
363	struct pmem_device *pmem;
364	struct request_queue *q;
365	struct device *gendev;
366	struct gendisk *disk;
367	void *addr;
368	int rc;
369	unsigned long flags = 0UL;
370
371	pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
372	if (!pmem)
373		return -ENOMEM;
374
 
 
 
 
375	/* while nsio_rw_bytes is active, parse a pfn info block if present */
376	if (is_nd_pfn(dev)) {
377		nd_pfn = to_nd_pfn(dev);
378		rc = nvdimm_setup_pfn(nd_pfn, &pmem->pgmap);
379		if (rc)
380			return rc;
381	}
382
383	/* we're attaching a block device, disable raw namespace access */
384	devm_nsio_disable(dev, nsio);
385
386	dev_set_drvdata(dev, pmem);
387	pmem->phys_addr = res->start;
388	pmem->size = resource_size(res);
389	fua = nvdimm_has_flush(nd_region);
390	if (!IS_ENABLED(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) || fua < 0) {
391		dev_warn(dev, "unable to guarantee persistence of writes\n");
392		fua = 0;
393	}
 
 
 
 
394
395	if (!devm_request_mem_region(dev, res->start, resource_size(res),
396				dev_name(&ndns->dev))) {
397		dev_warn(dev, "could not reserve region %pR\n", res);
398		return -EBUSY;
399	}
400
401	q = blk_alloc_queue_node(GFP_KERNEL, dev_to_node(dev));
402	if (!q)
403		return -ENOMEM;
404
 
 
405	pmem->pfn_flags = PFN_DEV;
406	pmem->pgmap.ref = &q->q_usage_counter;
407	if (is_nd_pfn(dev)) {
408		pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
409		pmem->pgmap.ops = &fsdax_pagemap_ops;
410		addr = devm_memremap_pages(dev, &pmem->pgmap);
411		pfn_sb = nd_pfn->pfn_sb;
412		pmem->data_offset = le64_to_cpu(pfn_sb->dataoff);
413		pmem->pfn_pad = resource_size(res) -
414			resource_size(&pmem->pgmap.res);
415		pmem->pfn_flags |= PFN_MAP;
416		memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res));
417		bb_res.start += pmem->data_offset;
418	} else if (pmem_should_map_pages(dev)) {
419		memcpy(&pmem->pgmap.res, &nsio->res, sizeof(pmem->pgmap.res));
 
 
420		pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
421		pmem->pgmap.ops = &fsdax_pagemap_ops;
422		addr = devm_memremap_pages(dev, &pmem->pgmap);
423		pmem->pfn_flags |= PFN_MAP;
424		memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res));
425	} else {
426		if (devm_add_action_or_reset(dev, pmem_release_queue,
427					&pmem->pgmap))
428			return -ENOMEM;
429		addr = devm_memremap(dev, pmem->phys_addr,
430				pmem->size, ARCH_MEMREMAP_PMEM);
431		memcpy(&bb_res, &nsio->res, sizeof(bb_res));
 
432	}
433
434	if (IS_ERR(addr))
435		return PTR_ERR(addr);
 
 
436	pmem->virt_addr = addr;
437
438	blk_queue_write_cache(q, true, fua);
439	blk_queue_make_request(q, pmem_make_request);
440	blk_queue_physical_block_size(q, PAGE_SIZE);
441	blk_queue_logical_block_size(q, pmem_sector_size(ndns));
442	blk_queue_max_hw_sectors(q, UINT_MAX);
443	blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
444	if (pmem->pfn_flags & PFN_MAP)
445		blk_queue_flag_set(QUEUE_FLAG_DAX, q);
446	q->queuedata = pmem;
447
448	disk = alloc_disk_node(0, nid);
449	if (!disk)
450		return -ENOMEM;
451	pmem->disk = disk;
452
453	disk->fops		= &pmem_fops;
454	disk->queue		= q;
455	disk->flags		= GENHD_FL_EXT_DEVT;
456	disk->queue->backing_dev_info->capabilities |= BDI_CAP_SYNCHRONOUS_IO;
457	nvdimm_namespace_disk_name(ndns, disk->disk_name);
458	set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset)
459			/ 512);
460	if (devm_init_badblocks(dev, &pmem->bb))
461		return -ENOMEM;
462	nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_res);
463	disk->bb = &pmem->bb;
464
465	if (is_nvdimm_sync(nd_region))
466		flags = DAXDEV_F_SYNC;
467	dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops, flags);
468	if (!dax_dev) {
469		put_disk(disk);
470		return -ENOMEM;
 
 
 
 
 
 
 
 
 
471	}
472	dax_write_cache(dax_dev, nvdimm_has_cache(nd_region));
473	pmem->dax_dev = dax_dev;
474	gendev = disk_to_dev(disk);
475	gendev->groups = pmem_attribute_groups;
476
477	device_add_disk(dev, disk, NULL);
478	if (devm_add_action_or_reset(dev, pmem_release_disk, pmem))
479		return -ENOMEM;
480
481	revalidate_disk(disk);
482
483	pmem->bb_state = sysfs_get_dirent(disk_to_dev(disk)->kobj.sd,
484					  "badblocks");
485	if (!pmem->bb_state)
486		dev_warn(dev, "'badblocks' notification disabled\n");
 
487
488	return 0;
 
 
 
 
 
 
 
489}
490
491static int nd_pmem_probe(struct device *dev)
492{
493	int ret;
494	struct nd_namespace_common *ndns;
495
496	ndns = nvdimm_namespace_common_probe(dev);
497	if (IS_ERR(ndns))
498		return PTR_ERR(ndns);
499
500	if (devm_nsio_enable(dev, to_nd_namespace_io(&ndns->dev)))
501		return -ENXIO;
502
503	if (is_nd_btt(dev))
504		return nvdimm_namespace_attach_btt(ndns);
505
506	if (is_nd_pfn(dev))
507		return pmem_attach_disk(dev, ndns);
508
 
 
 
 
509	ret = nd_btt_probe(dev, ndns);
510	if (ret == 0)
511		return -ENXIO;
512
513	/*
514	 * We have two failure conditions here, there is no
515	 * info reserver block or we found a valid info reserve block
516	 * but failed to initialize the pfn superblock.
517	 *
518	 * For the first case consider namespace as a raw pmem namespace
519	 * and attach a disk.
520	 *
521	 * For the latter, consider this a success and advance the namespace
522	 * seed.
523	 */
524	ret = nd_pfn_probe(dev, ndns);
525	if (ret == 0)
526		return -ENXIO;
527	else if (ret == -EOPNOTSUPP)
528		return ret;
529
530	ret = nd_dax_probe(dev, ndns);
531	if (ret == 0)
532		return -ENXIO;
533	else if (ret == -EOPNOTSUPP)
534		return ret;
 
 
 
 
535	return pmem_attach_disk(dev, ndns);
536}
537
538static int nd_pmem_remove(struct device *dev)
539{
540	struct pmem_device *pmem = dev_get_drvdata(dev);
541
542	if (is_nd_btt(dev))
543		nvdimm_namespace_detach_btt(to_nd_btt(dev));
544	else {
545		/*
546		 * Note, this assumes nd_device_lock() context to not
547		 * race nd_pmem_notify()
548		 */
549		sysfs_put(pmem->bb_state);
550		pmem->bb_state = NULL;
551	}
552	nvdimm_flush(to_nd_region(dev->parent), NULL);
553
554	return 0;
555}
556
557static void nd_pmem_shutdown(struct device *dev)
558{
559	nvdimm_flush(to_nd_region(dev->parent), NULL);
560}
561
562static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
563{
564	struct nd_region *nd_region;
565	resource_size_t offset = 0, end_trunc = 0;
566	struct nd_namespace_common *ndns;
567	struct nd_namespace_io *nsio;
568	struct resource res;
569	struct badblocks *bb;
 
570	struct kernfs_node *bb_state;
571
572	if (event != NVDIMM_REVALIDATE_POISON)
573		return;
574
575	if (is_nd_btt(dev)) {
576		struct nd_btt *nd_btt = to_nd_btt(dev);
577
578		ndns = nd_btt->ndns;
579		nd_region = to_nd_region(ndns->dev.parent);
580		nsio = to_nd_namespace_io(&ndns->dev);
581		bb = &nsio->bb;
582		bb_state = NULL;
583	} else {
584		struct pmem_device *pmem = dev_get_drvdata(dev);
585
586		nd_region = to_region(pmem);
587		bb = &pmem->bb;
588		bb_state = pmem->bb_state;
589
590		if (is_nd_pfn(dev)) {
591			struct nd_pfn *nd_pfn = to_nd_pfn(dev);
592			struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
593
594			ndns = nd_pfn->ndns;
595			offset = pmem->data_offset +
596					__le32_to_cpu(pfn_sb->start_pad);
597			end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
598		} else {
599			ndns = to_ndns(dev);
600		}
601
602		nsio = to_nd_namespace_io(&ndns->dev);
603	}
604
605	res.start = nsio->res.start + offset;
606	res.end = nsio->res.end - end_trunc;
607	nvdimm_badblocks_populate(nd_region, bb, &res);
608	if (bb_state)
609		sysfs_notify_dirent(bb_state);
610}
611
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
612MODULE_ALIAS("pmem");
613MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
614MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM);
615static struct nd_device_driver nd_pmem_driver = {
616	.probe = nd_pmem_probe,
617	.remove = nd_pmem_remove,
618	.notify = nd_pmem_notify,
619	.shutdown = nd_pmem_shutdown,
620	.drv = {
621		.name = "nd_pmem",
622	},
623	.type = ND_DRIVER_NAMESPACE_IO | ND_DRIVER_NAMESPACE_PMEM,
624};
625
626module_nd_driver(nd_pmem_driver);
627
628MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
 
629MODULE_LICENSE("GPL v2");