[linux.git] / drivers / nvdimm / blk.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * NVDIMM Block Window Driver
 * Copyright (c) 2014, Intel Corporation.
 */

#include <linux/blkdev.h>
#include <linux/fs.h>
#include <linux/genhd.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/nd.h>
#include <linux/sizes.h>
#include "nd.h"

static u32 nsblk_meta_size(struct nd_namespace_blk *nsblk)
{
	return nsblk->lbasize - ((nsblk->lbasize >= 4096) ? 4096 : 512);
}

static u32 nsblk_internal_lbasize(struct nd_namespace_blk *nsblk)
{
	return roundup(nsblk->lbasize, INT_LBASIZE_ALIGNMENT);
}

static u32 nsblk_sector_size(struct nd_namespace_blk *nsblk)
{
	return nsblk->lbasize - nsblk_meta_size(nsblk);
}

static resource_size_t to_dev_offset(struct nd_namespace_blk *nsblk,
				resource_size_t ns_offset, unsigned int len)
{
	int i;

	for (i = 0; i < nsblk->num_resources; i++) {
		if (ns_offset < resource_size(nsblk->res[i])) {
			if (ns_offset + len > resource_size(nsblk->res[i])) {
				dev_WARN_ONCE(&nsblk->common.dev, 1,
					"illegal request\n");
				return SIZE_MAX;
			}
			return nsblk->res[i]->start + ns_offset;
		}
		ns_offset -= resource_size(nsblk->res[i]);
	}

	dev_WARN_ONCE(&nsblk->common.dev, 1, "request out of range\n");
	return SIZE_MAX;
}

static struct nd_blk_region *to_ndbr(struct nd_namespace_blk *nsblk)
{
	struct nd_region *nd_region;
	struct device *parent;

	parent = nsblk->common.dev.parent;
	nd_region = container_of(parent, struct nd_region, dev);
	return container_of(nd_region, struct nd_blk_region, nd_region);
}

#ifdef CONFIG_BLK_DEV_INTEGRITY
static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk,
		struct bio_integrity_payload *bip, u64 lba, int rw)
{
	struct nd_blk_region *ndbr = to_ndbr(nsblk);
	unsigned int len = nsblk_meta_size(nsblk);
	resource_size_t	dev_offset, ns_offset;
	u32 internal_lbasize, sector_size;
	int err = 0;

	internal_lbasize = nsblk_internal_lbasize(nsblk);
	sector_size = nsblk_sector_size(nsblk);
	ns_offset = lba * internal_lbasize + sector_size;
	dev_offset = to_dev_offset(nsblk, ns_offset, len);
	if (dev_offset == SIZE_MAX)
		return -EIO;

	while (len) {
		unsigned int cur_len;
		struct bio_vec bv;
		void *iobuf;

		bv = bvec_iter_bvec(bip->bip_vec, bip->bip_iter);
		/*
		 * The 'bv' obtained from bvec_iter_bvec has its .bv_len and
		 * .bv_offset already adjusted for iter->bi_bvec_done, and we
		 * can use those directly
		 */

		cur_len = min(len, bv.bv_len);
		iobuf = kmap_atomic(bv.bv_page);
		err = ndbr->do_io(ndbr, dev_offset, iobuf + bv.bv_offset,
				cur_len, rw);
		kunmap_atomic(iobuf);
		if (err)
			return err;

		len -= cur_len;
		dev_offset += cur_len;
		if (!bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len))
			return -EIO;
	}

	return err;
}

#else /* CONFIG_BLK_DEV_INTEGRITY */
static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk,
		struct bio_integrity_payload *bip, u64 lba, int rw)
{
	return 0;
}
#endif

static int nsblk_do_bvec(struct nd_namespace_blk *nsblk,
		struct bio_integrity_payload *bip, struct page *page,
		unsigned int len, unsigned int off, int rw, sector_t sector)
{
	struct nd_blk_region *ndbr = to_ndbr(nsblk);
	resource_size_t	dev_offset, ns_offset;
	u32 internal_lbasize, sector_size;
	int err = 0;
	void *iobuf;
	u64 lba;

	internal_lbasize = nsblk_internal_lbasize(nsblk);
	sector_size = nsblk_sector_size(nsblk);
	while (len) {
		unsigned int cur_len;

		/*
		 * If we don't have an integrity payload, we don't have to
		 * split the bvec into sectors, as this would cause unnecessary
		 * Block Window setup/move steps. the do_io routine is capable
		 * of handling len <= PAGE_SIZE.
		 */
		cur_len = bip ? min(len, sector_size) : len;

		lba = div_u64(sector << SECTOR_SHIFT, sector_size);
		ns_offset = lba * internal_lbasize;
		dev_offset = to_dev_offset(nsblk, ns_offset, cur_len);
		if (dev_offset == SIZE_MAX)
			return -EIO;

		iobuf = kmap_atomic(page);
		err = ndbr->do_io(ndbr, dev_offset, iobuf + off, cur_len, rw);
		kunmap_atomic(iobuf);
		if (err)
			return err;

		if (bip) {
			err = nd_blk_rw_integrity(nsblk, bip, lba, rw);
			if (err)
				return err;
		}
		len -= cur_len;
		off += cur_len;
		sector += sector_size >> SECTOR_SHIFT;
	}

	return err;
}

static blk_qc_t nd_blk_make_request(struct request_queue *q, struct bio *bio)
{
	struct bio_integrity_payload *bip;
	struct nd_namespace_blk *nsblk;
	struct bvec_iter iter;
	unsigned long start;
	struct bio_vec bvec;
	int err = 0, rw;
	bool do_acct;

	if (!bio_integrity_prep(bio))
		return BLK_QC_T_NONE;

	bip = bio_integrity(bio);
	nsblk = q->queuedata;
	rw = bio_data_dir(bio);
	do_acct = blk_queue_io_stat(bio->bi_disk->queue);
	if (do_acct)
		start = bio_start_io_acct(bio);
	bio_for_each_segment(bvec, bio, iter) {
		unsigned int len = bvec.bv_len;

		BUG_ON(len > PAGE_SIZE);
		err = nsblk_do_bvec(nsblk, bip, bvec.bv_page, len,
				bvec.bv_offset, rw, iter.bi_sector);
		if (err) {
			dev_dbg(&nsblk->common.dev,
					"io error in %s sector %lld, len %d,\n",
					(rw == READ) ? "READ" : "WRITE",
					(unsigned long long) iter.bi_sector, len);
			bio->bi_status = errno_to_blk_status(err);
			break;
		}
	}
	if (do_acct)
		bio_end_io_acct(bio, start);

	bio_endio(bio);
	return BLK_QC_T_NONE;
}

static int nsblk_rw_bytes(struct nd_namespace_common *ndns,
		resource_size_t offset, void *iobuf, size_t n, int rw,
		unsigned long flags)
{
	struct nd_namespace_blk *nsblk = to_nd_namespace_blk(&ndns->dev);
	struct nd_blk_region *ndbr = to_ndbr(nsblk);
	resource_size_t	dev_offset;

	dev_offset = to_dev_offset(nsblk, offset, n);

	if (unlikely(offset + n > nsblk->size)) {
		dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
		return -EFAULT;
	}

	if (dev_offset == SIZE_MAX)
		return -EIO;

	return ndbr->do_io(ndbr, dev_offset, iobuf, n, rw);
}

static const struct block_device_operations nd_blk_fops = {
	.owner = THIS_MODULE,
	.revalidate_disk = nvdimm_revalidate_disk,
};

static void nd_blk_release_queue(void *q)
{
	blk_cleanup_queue(q);
}

static void nd_blk_release_disk(void *disk)
{
	del_gendisk(disk);
	put_disk(disk);
}

static int nsblk_attach_disk(struct nd_namespace_blk *nsblk)
{
	struct device *dev = &nsblk->common.dev;
	resource_size_t available_disk_size;
	struct request_queue *q;
	struct gendisk *disk;
	u64 internal_nlba;

	internal_nlba = div_u64(nsblk->size, nsblk_internal_lbasize(nsblk));
	available_disk_size = internal_nlba * nsblk_sector_size(nsblk);

	q = blk_alloc_queue(nd_blk_make_request, NUMA_NO_NODE);
	if (!q)
		return -ENOMEM;
	if (devm_add_action_or_reset(dev, nd_blk_release_queue, q))
		return -ENOMEM;

	blk_queue_max_hw_sectors(q, UINT_MAX);
	blk_queue_logical_block_size(q, nsblk_sector_size(nsblk));
	blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
	q->queuedata = nsblk;

	disk = alloc_disk(0);
	if (!disk)
		return -ENOMEM;

	disk->first_minor	= 0;
	disk->fops		= &nd_blk_fops;
	disk->queue		= q;
	disk->flags		= GENHD_FL_EXT_DEVT;
	nvdimm_namespace_disk_name(&nsblk->common, disk->disk_name);

	if (devm_add_action_or_reset(dev, nd_blk_release_disk, disk))
		return -ENOMEM;

	if (nsblk_meta_size(nsblk)) {
		int rc = nd_integrity_init(disk, nsblk_meta_size(nsblk));

		if (rc)
			return rc;
	}

	set_capacity(disk, available_disk_size >> SECTOR_SHIFT);
	device_add_disk(dev, disk, NULL);
	revalidate_disk(disk);
	return 0;
}

static int nd_blk_probe(struct device *dev)
{
	struct nd_namespace_common *ndns;
	struct nd_namespace_blk *nsblk;

	ndns = nvdimm_namespace_common_probe(dev);
	if (IS_ERR(ndns))
		return PTR_ERR(ndns);

	nsblk = to_nd_namespace_blk(&ndns->dev);
	nsblk->size = nvdimm_namespace_capacity(ndns);
	dev_set_drvdata(dev, nsblk);

	ndns->rw_bytes = nsblk_rw_bytes;
	if (is_nd_btt(dev))
		return nvdimm_namespace_attach_btt(ndns);
	else if (nd_btt_probe(dev, ndns) == 0) {
		/* we'll come back as btt-blk */
		return -ENXIO;
	} else
		return nsblk_attach_disk(nsblk);
}

static int nd_blk_remove(struct device *dev)
{
	if (is_nd_btt(dev))
		nvdimm_namespace_detach_btt(to_nd_btt(dev));
	return 0;
}

static struct nd_device_driver nd_blk_driver = {
	.probe = nd_blk_probe,
	.remove = nd_blk_remove,
	.drv = {
		.name = "nd_blk",
	},
	.type = ND_DRIVER_NAMESPACE_BLK,
};

static int __init nd_blk_init(void)
{
	return nd_driver_register(&nd_blk_driver);
}

static void __exit nd_blk_exit(void)
{
	driver_unregister(&nd_blk_driver.drv);
}

MODULE_AUTHOR("Ross Zwisler <[email protected]>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_BLK);
module_init(nd_blk_init);
module_exit(nd_blk_exit);
Commit	Line	Data
2025cf9e	1	// SPDX-License-Identifier: GPL-2.0-only
047fc8a1 RZ	2	/*
	3	* NVDIMM Block Window Driver
	4	* Copyright (c) 2014, Intel Corporation.
047fc8a1 RZ	5	*/
	6
	7	#include <linux/blkdev.h>
	8	#include <linux/fs.h>
	9	#include <linux/genhd.h>
	10	#include <linux/module.h>
	11	#include <linux/moduleparam.h>
	12	#include <linux/nd.h>
	13	#include <linux/sizes.h>
	14	#include "nd.h"
	15
9d90725d DW	16	static u32 nsblk_meta_size(struct nd_namespace_blk *nsblk)
	17	{
	18	return nsblk->lbasize - ((nsblk->lbasize >= 4096) ? 4096 : 512);
	19	}
047fc8a1	20
9d90725d	21	static u32 nsblk_internal_lbasize(struct nd_namespace_blk *nsblk)
fcae6957	22	{
9d90725d DW	23	return roundup(nsblk->lbasize, INT_LBASIZE_ALIGNMENT);
	24	}
	25
	26	static u32 nsblk_sector_size(struct nd_namespace_blk *nsblk)
	27	{
	28	return nsblk->lbasize - nsblk_meta_size(nsblk);
fcae6957 VV	29	}
fcae6957 VV	30
047fc8a1 RZ	31	static resource_size_t to_dev_offset(struct nd_namespace_blk *nsblk,
	32	resource_size_t ns_offset, unsigned int len)
	33	{
	34	int i;
	35
	36	for (i = 0; i < nsblk->num_resources; i++) {
	37	if (ns_offset < resource_size(nsblk->res[i])) {
	38	if (ns_offset + len > resource_size(nsblk->res[i])) {
	39	dev_WARN_ONCE(&nsblk->common.dev, 1,
	40	"illegal request\n");
	41	return SIZE_MAX;
	42	}
	43	return nsblk->res[i]->start + ns_offset;
	44	}
	45	ns_offset -= resource_size(nsblk->res[i]);
	46	}
	47
	48	dev_WARN_ONCE(&nsblk->common.dev, 1, "request out of range\n");
	49	return SIZE_MAX;
	50	}
	51
9d90725d DW	52	static struct nd_blk_region to_ndbr(struct nd_namespace_blk nsblk)
	53	{
	54	struct nd_region *nd_region;
	55	struct device *parent;
	56
	57	parent = nsblk->common.dev.parent;
	58	nd_region = container_of(parent, struct nd_region, dev);
	59	return container_of(nd_region, struct nd_blk_region, nd_region);
	60	}
	61
fcae6957	62	#ifdef CONFIG_BLK_DEV_INTEGRITY
9d90725d DW	63	static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk,
9d90725d DW	64	struct bio_integrity_payload *bip, u64 lba, int rw)
fcae6957	65	{
9d90725d DW	66	struct nd_blk_region *ndbr = to_ndbr(nsblk);
9d90725d DW	67	unsigned int len = nsblk_meta_size(nsblk);
fcae6957	68	resource_size_t dev_offset, ns_offset;
9d90725d	69	u32 internal_lbasize, sector_size;
fcae6957 VV	70	int err = 0;
fcae6957 VV	71
9d90725d DW	72	internal_lbasize = nsblk_internal_lbasize(nsblk);
	73	sector_size = nsblk_sector_size(nsblk);
	74	ns_offset = lba * internal_lbasize + sector_size;
fcae6957 VV	75	dev_offset = to_dev_offset(nsblk, ns_offset, len);
	76	if (dev_offset == SIZE_MAX)
	77	return -EIO;
	78
	79	while (len) {
	80	unsigned int cur_len;
	81	struct bio_vec bv;
	82	void *iobuf;
	83
	84	bv = bvec_iter_bvec(bip->bip_vec, bip->bip_iter);
	85	/*
	86	* The 'bv' obtained from bvec_iter_bvec has its .bv_len and
	87	* .bv_offset already adjusted for iter->bi_bvec_done, and we
	88	* can use those directly
	89	*/
	90
	91	cur_len = min(len, bv.bv_len);
	92	iobuf = kmap_atomic(bv.bv_page);
	93	err = ndbr->do_io(ndbr, dev_offset, iobuf + bv.bv_offset,
	94	cur_len, rw);
	95	kunmap_atomic(iobuf);
	96	if (err)
	97	return err;
	98
	99	len -= cur_len;
	100	dev_offset += cur_len;
b1fb2c52 DM	101	if (!bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len))
b1fb2c52 DM	102	return -EIO;
fcae6957 VV	103	}
	104
	105	return err;
	106	}
	107
	108	#else /* CONFIG_BLK_DEV_INTEGRITY */
9d90725d DW	109	static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk,
9d90725d DW	110	struct bio_integrity_payload *bip, u64 lba, int rw)
fcae6957 VV	111	{
	112	return 0;
	113	}
	114	#endif
	115
9d90725d DW	116	static int nsblk_do_bvec(struct nd_namespace_blk *nsblk,
	117	struct bio_integrity_payload bip, struct page page,
	118	unsigned int len, unsigned int off, int rw, sector_t sector)
fcae6957	119	{
9d90725d	120	struct nd_blk_region *ndbr = to_ndbr(nsblk);
fcae6957	121	resource_size_t dev_offset, ns_offset;
9d90725d	122	u32 internal_lbasize, sector_size;
fcae6957 VV	123	int err = 0;
	124	void *iobuf;
	125	u64 lba;
	126
9d90725d DW	127	internal_lbasize = nsblk_internal_lbasize(nsblk);
9d90725d DW	128	sector_size = nsblk_sector_size(nsblk);
fcae6957 VV	129	while (len) {
	130	unsigned int cur_len;
	131
	132	/*
	133	* If we don't have an integrity payload, we don't have to
	134	* split the bvec into sectors, as this would cause unnecessary
	135	* Block Window setup/move steps. the do_io routine is capable
	136	* of handling len <= PAGE_SIZE.
	137	*/
9d90725d	138	cur_len = bip ? min(len, sector_size) : len;
fcae6957	139
9d90725d DW	140	lba = div_u64(sector << SECTOR_SHIFT, sector_size);
	141	ns_offset = lba * internal_lbasize;
	142	dev_offset = to_dev_offset(nsblk, ns_offset, cur_len);
fcae6957 VV	143	if (dev_offset == SIZE_MAX)
	144	return -EIO;
	145
	146	iobuf = kmap_atomic(page);
	147	err = ndbr->do_io(ndbr, dev_offset, iobuf + off, cur_len, rw);
	148	kunmap_atomic(iobuf);
	149	if (err)
	150	return err;
	151
	152	if (bip) {
9d90725d	153	err = nd_blk_rw_integrity(nsblk, bip, lba, rw);
fcae6957 VV	154	if (err)
	155	return err;
	156	}
	157	len -= cur_len;
	158	off += cur_len;
9d90725d	159	sector += sector_size >> SECTOR_SHIFT;
fcae6957 VV	160	}
	161
	162	return err;
	163	}
	164
dece1635	165	static blk_qc_t nd_blk_make_request(struct request_queue q, struct bio bio)
047fc8a1	166	{
fcae6957	167	struct bio_integrity_payload *bip;
9d90725d	168	struct nd_namespace_blk *nsblk;
047fc8a1	169	struct bvec_iter iter;
f0dc089c	170	unsigned long start;
047fc8a1 RZ	171	struct bio_vec bvec;
047fc8a1 RZ	172	int err = 0, rw;
f0dc089c	173	bool do_acct;
047fc8a1	174
e23947bd DM	175	if (!bio_integrity_prep(bio))
e23947bd DM	176	return BLK_QC_T_NONE;
fcae6957 VV	177
fcae6957 VV	178	bip = bio_integrity(bio);
9d90725d	179	nsblk = q->queuedata;
047fc8a1	180	rw = bio_data_dir(bio);
0fd92f89 CH	181	do_acct = blk_queue_io_stat(bio->bi_disk->queue);
	182	if (do_acct)
	183	start = bio_start_io_acct(bio);
047fc8a1 RZ	184	bio_for_each_segment(bvec, bio, iter) {
047fc8a1 RZ	185	unsigned int len = bvec.bv_len;
047fc8a1 RZ	186
047fc8a1 RZ	187	BUG_ON(len > PAGE_SIZE);
9d90725d DW	188	err = nsblk_do_bvec(nsblk, bip, bvec.bv_page, len,
9d90725d DW	189	bvec.bv_offset, rw, iter.bi_sector);
fcae6957	190	if (err) {
9d90725d	191	dev_dbg(&nsblk->common.dev,
fcae6957 VV	192	"io error in %s sector %lld, len %d,\n",
	193	(rw == READ) ? "READ" : "WRITE",
	194	(unsigned long long) iter.bi_sector, len);
4e4cbee9	195	bio->bi_status = errno_to_blk_status(err);
f0dc089c	196	break;
047fc8a1	197	}
047fc8a1	198	}
f0dc089c	199	if (do_acct)
0fd92f89	200	bio_end_io_acct(bio, start);
047fc8a1	201
4246a0b6	202	bio_endio(bio);
dece1635	203	return BLK_QC_T_NONE;
047fc8a1 RZ	204	}
047fc8a1 RZ	205
9d90725d	206	static int nsblk_rw_bytes(struct nd_namespace_common *ndns,
3ae3d67b VV	207	resource_size_t offset, void *iobuf, size_t n, int rw,
3ae3d67b VV	208	unsigned long flags)
047fc8a1	209	{
9d90725d DW	210	struct nd_namespace_blk *nsblk = to_nd_namespace_blk(&ndns->dev);
9d90725d DW	211	struct nd_blk_region *ndbr = to_ndbr(nsblk);
047fc8a1 RZ	212	resource_size_t dev_offset;
	213
	214	dev_offset = to_dev_offset(nsblk, offset, n);
	215
9d90725d	216	if (unlikely(offset + n > nsblk->size)) {
047fc8a1 RZ	217	dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
	218	return -EFAULT;
	219	}
	220
	221	if (dev_offset == SIZE_MAX)
	222	return -EIO;
	223
	224	return ndbr->do_io(ndbr, dev_offset, iobuf, n, rw);
	225	}
	226
	227	static const struct block_device_operations nd_blk_fops = {
	228	.owner = THIS_MODULE,
58138820	229	.revalidate_disk = nvdimm_revalidate_disk,
047fc8a1 RZ	230	};
047fc8a1 RZ	231
d29cee12 DW	232	static void nd_blk_release_queue(void *q)
	233	{
	234	blk_cleanup_queue(q);
	235	}
	236
	237	static void nd_blk_release_disk(void *disk)
	238	{
	239	del_gendisk(disk);
	240	put_disk(disk);
	241	}
	242
9d90725d	243	static int nsblk_attach_disk(struct nd_namespace_blk *nsblk)
047fc8a1	244	{
9d90725d	245	struct device *dev = &nsblk->common.dev;
fcae6957	246	resource_size_t available_disk_size;
d29cee12	247	struct request_queue *q;
047fc8a1	248	struct gendisk *disk;
fcae6957 VV	249	u64 internal_nlba;
fcae6957 VV	250
9d90725d DW	251	internal_nlba = div_u64(nsblk->size, nsblk_internal_lbasize(nsblk));
9d90725d DW	252	available_disk_size = internal_nlba * nsblk_sector_size(nsblk);
047fc8a1	253
3d745ea5	254	q = blk_alloc_queue(nd_blk_make_request, NUMA_NO_NODE);
d29cee12 DW	255	if (!q)
d29cee12 DW	256	return -ENOMEM;
f02716db	257	if (devm_add_action_or_reset(dev, nd_blk_release_queue, q))
047fc8a1 RZ	258	return -ENOMEM;
047fc8a1 RZ	259
d29cee12	260	blk_queue_max_hw_sectors(q, UINT_MAX);
9d90725d	261	blk_queue_logical_block_size(q, nsblk_sector_size(nsblk));
8b904b5b	262	blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
9d90725d	263	q->queuedata = nsblk;
047fc8a1	264
d29cee12 DW	265	disk = alloc_disk(0);
	266	if (!disk)
	267	return -ENOMEM;
047fc8a1	268
047fc8a1 RZ	269	disk->first_minor = 0;
047fc8a1 RZ	270	disk->fops = &nd_blk_fops;
d29cee12	271	disk->queue = q;
047fc8a1	272	disk->flags = GENHD_FL_EXT_DEVT;
9d90725d	273	nvdimm_namespace_disk_name(&nsblk->common, disk->disk_name);
047fc8a1	274
f02716db DW	275	if (devm_add_action_or_reset(dev, nd_blk_release_disk, disk))
	276	return -ENOMEM;
	277
9d90725d DW	278	if (nsblk_meta_size(nsblk)) {
9d90725d DW	279	int rc = nd_integrity_init(disk, nsblk_meta_size(nsblk));
fcae6957	280
d29cee12	281	if (rc)
fcae6957	282	return rc;
fcae6957 VV	283	}
	284
	285	set_capacity(disk, available_disk_size >> SECTOR_SHIFT);
fef912bf	286	device_add_disk(dev, disk, NULL);
58138820	287	revalidate_disk(disk);
047fc8a1 RZ	288	return 0;
	289	}
	290
	291	static int nd_blk_probe(struct device *dev)
	292	{
	293	struct nd_namespace_common *ndns;
fcae6957	294	struct nd_namespace_blk *nsblk;
047fc8a1 RZ	295
	296	ndns = nvdimm_namespace_common_probe(dev);
	297	if (IS_ERR(ndns))
	298	return PTR_ERR(ndns);
	299
fcae6957	300	nsblk = to_nd_namespace_blk(&ndns->dev);
9d90725d DW	301	nsblk->size = nvdimm_namespace_capacity(ndns);
	302	dev_set_drvdata(dev, nsblk);
	303
	304	ndns->rw_bytes = nsblk_rw_bytes;
047fc8a1	305	if (is_nd_btt(dev))
d29cee12	306	return nvdimm_namespace_attach_btt(ndns);
200c79da	307	else if (nd_btt_probe(dev, ndns) == 0) {
047fc8a1	308	/* we'll come back as btt-blk */
d29cee12	309	return -ENXIO;
047fc8a1	310	} else
9d90725d	311	return nsblk_attach_disk(nsblk);
047fc8a1 RZ	312	}
	313
	314	static int nd_blk_remove(struct device *dev)
	315	{
047fc8a1	316	if (is_nd_btt(dev))
298f2bc5	317	nvdimm_namespace_detach_btt(to_nd_btt(dev));
047fc8a1 RZ	318	return 0;
	319	}
	320
	321	static struct nd_device_driver nd_blk_driver = {
	322	.probe = nd_blk_probe,
	323	.remove = nd_blk_remove,
	324	.drv = {
	325	.name = "nd_blk",
	326	},
	327	.type = ND_DRIVER_NAMESPACE_BLK,
	328	};
	329
	330	static int __init nd_blk_init(void)
	331	{
ec56151d	332	return nd_driver_register(&nd_blk_driver);
047fc8a1 RZ	333	}
	334
	335	static void __exit nd_blk_exit(void)
	336	{
	337	driver_unregister(&nd_blk_driver.drv);
047fc8a1 RZ	338	}
	339
	340	MODULE_AUTHOR("Ross Zwisler <[email protected]>");
	341	MODULE_LICENSE("GPL v2");
	342	MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_BLK);
	343	module_init(nd_blk_init);
	344	module_exit(nd_blk_exit);