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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * NVDIMM Block Window Driver
4 * Copyright (c) 2014, Intel Corporation.
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
16static u32 nsblk_meta_size(struct nd_namespace_blk *nsblk)
17{
18 return nsblk->lbasize - ((nsblk->lbasize >= 4096) ? 4096 : 512);
19}
20
21static u32 nsblk_internal_lbasize(struct nd_namespace_blk *nsblk)
22{
23 return roundup(nsblk->lbasize, INT_LBASIZE_ALIGNMENT);
24}
25
26static u32 nsblk_sector_size(struct nd_namespace_blk *nsblk)
27{
28 return nsblk->lbasize - nsblk_meta_size(nsblk);
29}
30
31static 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
52static 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
62#ifdef CONFIG_BLK_DEV_INTEGRITY
63static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk,
64 struct bio_integrity_payload *bip, u64 lba, int rw)
65{
66 struct nd_blk_region *ndbr = to_ndbr(nsblk);
67 unsigned int len = nsblk_meta_size(nsblk);
68 resource_size_t dev_offset, ns_offset;
69 u32 internal_lbasize, sector_size;
70 int err = 0;
71
72 internal_lbasize = nsblk_internal_lbasize(nsblk);
73 sector_size = nsblk_sector_size(nsblk);
74 ns_offset = lba * internal_lbasize + sector_size;
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;
101 if (!bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len))
102 return -EIO;
103 }
104
105 return err;
106}
107
108#else /* CONFIG_BLK_DEV_INTEGRITY */
109static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk,
110 struct bio_integrity_payload *bip, u64 lba, int rw)
111{
112 return 0;
113}
114#endif
115
116static 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)
119{
120 struct nd_blk_region *ndbr = to_ndbr(nsblk);
121 resource_size_t dev_offset, ns_offset;
122 u32 internal_lbasize, sector_size;
123 int err = 0;
124 void *iobuf;
125 u64 lba;
126
127 internal_lbasize = nsblk_internal_lbasize(nsblk);
128 sector_size = nsblk_sector_size(nsblk);
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 */
138 cur_len = bip ? min(len, sector_size) : len;
139
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);
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) {
153 err = nd_blk_rw_integrity(nsblk, bip, lba, rw);
154 if (err)
155 return err;
156 }
157 len -= cur_len;
158 off += cur_len;
159 sector += sector_size >> SECTOR_SHIFT;
160 }
161
162 return err;
163}
164
165static blk_qc_t nd_blk_submit_bio(struct bio *bio)
166{
167 struct bio_integrity_payload *bip;
168 struct nd_namespace_blk *nsblk = bio->bi_disk->private_data;
169 struct bvec_iter iter;
170 unsigned long start;
171 struct bio_vec bvec;
172 int err = 0, rw;
173 bool do_acct;
174
175 if (!bio_integrity_prep(bio))
176 return BLK_QC_T_NONE;
177
178 bip = bio_integrity(bio);
179 rw = bio_data_dir(bio);
180 do_acct = blk_queue_io_stat(bio->bi_disk->queue);
181 if (do_acct)
182 start = bio_start_io_acct(bio);
183 bio_for_each_segment(bvec, bio, iter) {
184 unsigned int len = bvec.bv_len;
185
186 BUG_ON(len > PAGE_SIZE);
187 err = nsblk_do_bvec(nsblk, bip, bvec.bv_page, len,
188 bvec.bv_offset, rw, iter.bi_sector);
189 if (err) {
190 dev_dbg(&nsblk->common.dev,
191 "io error in %s sector %lld, len %d,\n",
192 (rw == READ) ? "READ" : "WRITE",
193 (unsigned long long) iter.bi_sector, len);
194 bio->bi_status = errno_to_blk_status(err);
195 break;
196 }
197 }
198 if (do_acct)
199 bio_end_io_acct(bio, start);
200
201 bio_endio(bio);
202 return BLK_QC_T_NONE;
203}
204
205static int nsblk_rw_bytes(struct nd_namespace_common *ndns,
206 resource_size_t offset, void *iobuf, size_t n, int rw,
207 unsigned long flags)
208{
209 struct nd_namespace_blk *nsblk = to_nd_namespace_blk(&ndns->dev);
210 struct nd_blk_region *ndbr = to_ndbr(nsblk);
211 resource_size_t dev_offset;
212
213 dev_offset = to_dev_offset(nsblk, offset, n);
214
215 if (unlikely(offset + n > nsblk->size)) {
216 dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
217 return -EFAULT;
218 }
219
220 if (dev_offset == SIZE_MAX)
221 return -EIO;
222
223 return ndbr->do_io(ndbr, dev_offset, iobuf, n, rw);
224}
225
226static const struct block_device_operations nd_blk_fops = {
227 .owner = THIS_MODULE,
228 .submit_bio = nd_blk_submit_bio,
229 .revalidate_disk = nvdimm_revalidate_disk,
230};
231
232static void nd_blk_release_queue(void *q)
233{
234 blk_cleanup_queue(q);
235}
236
237static void nd_blk_release_disk(void *disk)
238{
239 del_gendisk(disk);
240 put_disk(disk);
241}
242
243static int nsblk_attach_disk(struct nd_namespace_blk *nsblk)
244{
245 struct device *dev = &nsblk->common.dev;
246 resource_size_t available_disk_size;
247 struct request_queue *q;
248 struct gendisk *disk;
249 u64 internal_nlba;
250
251 internal_nlba = div_u64(nsblk->size, nsblk_internal_lbasize(nsblk));
252 available_disk_size = internal_nlba * nsblk_sector_size(nsblk);
253
254 q = blk_alloc_queue(NUMA_NO_NODE);
255 if (!q)
256 return -ENOMEM;
257 if (devm_add_action_or_reset(dev, nd_blk_release_queue, q))
258 return -ENOMEM;
259
260 blk_queue_max_hw_sectors(q, UINT_MAX);
261 blk_queue_logical_block_size(q, nsblk_sector_size(nsblk));
262 blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
263
264 disk = alloc_disk(0);
265 if (!disk)
266 return -ENOMEM;
267
268 disk->first_minor = 0;
269 disk->fops = &nd_blk_fops;
270 disk->queue = q;
271 disk->flags = GENHD_FL_EXT_DEVT;
272 disk->private_data = nsblk;
273 nvdimm_namespace_disk_name(&nsblk->common, disk->disk_name);
274
275 if (devm_add_action_or_reset(dev, nd_blk_release_disk, disk))
276 return -ENOMEM;
277
278 if (nsblk_meta_size(nsblk)) {
279 int rc = nd_integrity_init(disk, nsblk_meta_size(nsblk));
280
281 if (rc)
282 return rc;
283 }
284
285 set_capacity(disk, available_disk_size >> SECTOR_SHIFT);
286 device_add_disk(dev, disk, NULL);
287 revalidate_disk(disk);
288 return 0;
289}
290
291static int nd_blk_probe(struct device *dev)
292{
293 struct nd_namespace_common *ndns;
294 struct nd_namespace_blk *nsblk;
295
296 ndns = nvdimm_namespace_common_probe(dev);
297 if (IS_ERR(ndns))
298 return PTR_ERR(ndns);
299
300 nsblk = to_nd_namespace_blk(&ndns->dev);
301 nsblk->size = nvdimm_namespace_capacity(ndns);
302 dev_set_drvdata(dev, nsblk);
303
304 ndns->rw_bytes = nsblk_rw_bytes;
305 if (is_nd_btt(dev))
306 return nvdimm_namespace_attach_btt(ndns);
307 else if (nd_btt_probe(dev, ndns) == 0) {
308 /* we'll come back as btt-blk */
309 return -ENXIO;
310 } else
311 return nsblk_attach_disk(nsblk);
312}
313
314static int nd_blk_remove(struct device *dev)
315{
316 if (is_nd_btt(dev))
317 nvdimm_namespace_detach_btt(to_nd_btt(dev));
318 return 0;
319}
320
321static 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
330static int __init nd_blk_init(void)
331{
332 return nd_driver_register(&nd_blk_driver);
333}
334
335static void __exit nd_blk_exit(void)
336{
337 driver_unregister(&nd_blk_driver.drv);
338}
339
340MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
341MODULE_LICENSE("GPL v2");
342MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_BLK);
343module_init(nd_blk_init);
344module_exit(nd_blk_exit);
1/*
2 * NVDIMM Block Window Driver
3 * Copyright (c) 2014, Intel Corporation.
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 */
14
15#include <linux/blkdev.h>
16#include <linux/fs.h>
17#include <linux/genhd.h>
18#include <linux/module.h>
19#include <linux/moduleparam.h>
20#include <linux/nd.h>
21#include <linux/sizes.h>
22#include "nd.h"
23
24struct nd_blk_device {
25 struct request_queue *queue;
26 struct gendisk *disk;
27 struct nd_namespace_blk *nsblk;
28 struct nd_blk_region *ndbr;
29 size_t disk_size;
30 u32 sector_size;
31 u32 internal_lbasize;
32};
33
34static u32 nd_blk_meta_size(struct nd_blk_device *blk_dev)
35{
36 return blk_dev->nsblk->lbasize - blk_dev->sector_size;
37}
38
39static resource_size_t to_dev_offset(struct nd_namespace_blk *nsblk,
40 resource_size_t ns_offset, unsigned int len)
41{
42 int i;
43
44 for (i = 0; i < nsblk->num_resources; i++) {
45 if (ns_offset < resource_size(nsblk->res[i])) {
46 if (ns_offset + len > resource_size(nsblk->res[i])) {
47 dev_WARN_ONCE(&nsblk->common.dev, 1,
48 "illegal request\n");
49 return SIZE_MAX;
50 }
51 return nsblk->res[i]->start + ns_offset;
52 }
53 ns_offset -= resource_size(nsblk->res[i]);
54 }
55
56 dev_WARN_ONCE(&nsblk->common.dev, 1, "request out of range\n");
57 return SIZE_MAX;
58}
59
60#ifdef CONFIG_BLK_DEV_INTEGRITY
61static int nd_blk_rw_integrity(struct nd_blk_device *blk_dev,
62 struct bio_integrity_payload *bip, u64 lba,
63 int rw)
64{
65 unsigned int len = nd_blk_meta_size(blk_dev);
66 resource_size_t dev_offset, ns_offset;
67 struct nd_namespace_blk *nsblk;
68 struct nd_blk_region *ndbr;
69 int err = 0;
70
71 nsblk = blk_dev->nsblk;
72 ndbr = blk_dev->ndbr;
73 ns_offset = lba * blk_dev->internal_lbasize + blk_dev->sector_size;
74 dev_offset = to_dev_offset(nsblk, ns_offset, len);
75 if (dev_offset == SIZE_MAX)
76 return -EIO;
77
78 while (len) {
79 unsigned int cur_len;
80 struct bio_vec bv;
81 void *iobuf;
82
83 bv = bvec_iter_bvec(bip->bip_vec, bip->bip_iter);
84 /*
85 * The 'bv' obtained from bvec_iter_bvec has its .bv_len and
86 * .bv_offset already adjusted for iter->bi_bvec_done, and we
87 * can use those directly
88 */
89
90 cur_len = min(len, bv.bv_len);
91 iobuf = kmap_atomic(bv.bv_page);
92 err = ndbr->do_io(ndbr, dev_offset, iobuf + bv.bv_offset,
93 cur_len, rw);
94 kunmap_atomic(iobuf);
95 if (err)
96 return err;
97
98 len -= cur_len;
99 dev_offset += cur_len;
100 bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len);
101 }
102
103 return err;
104}
105
106#else /* CONFIG_BLK_DEV_INTEGRITY */
107static int nd_blk_rw_integrity(struct nd_blk_device *blk_dev,
108 struct bio_integrity_payload *bip, u64 lba,
109 int rw)
110{
111 return 0;
112}
113#endif
114
115static int nd_blk_do_bvec(struct nd_blk_device *blk_dev,
116 struct bio_integrity_payload *bip, struct page *page,
117 unsigned int len, unsigned int off, int rw,
118 sector_t sector)
119{
120 struct nd_blk_region *ndbr = blk_dev->ndbr;
121 resource_size_t dev_offset, ns_offset;
122 int err = 0;
123 void *iobuf;
124 u64 lba;
125
126 while (len) {
127 unsigned int cur_len;
128
129 /*
130 * If we don't have an integrity payload, we don't have to
131 * split the bvec into sectors, as this would cause unnecessary
132 * Block Window setup/move steps. the do_io routine is capable
133 * of handling len <= PAGE_SIZE.
134 */
135 cur_len = bip ? min(len, blk_dev->sector_size) : len;
136
137 lba = div_u64(sector << SECTOR_SHIFT, blk_dev->sector_size);
138 ns_offset = lba * blk_dev->internal_lbasize;
139 dev_offset = to_dev_offset(blk_dev->nsblk, ns_offset, cur_len);
140 if (dev_offset == SIZE_MAX)
141 return -EIO;
142
143 iobuf = kmap_atomic(page);
144 err = ndbr->do_io(ndbr, dev_offset, iobuf + off, cur_len, rw);
145 kunmap_atomic(iobuf);
146 if (err)
147 return err;
148
149 if (bip) {
150 err = nd_blk_rw_integrity(blk_dev, bip, lba, rw);
151 if (err)
152 return err;
153 }
154 len -= cur_len;
155 off += cur_len;
156 sector += blk_dev->sector_size >> SECTOR_SHIFT;
157 }
158
159 return err;
160}
161
162static blk_qc_t nd_blk_make_request(struct request_queue *q, struct bio *bio)
163{
164 struct block_device *bdev = bio->bi_bdev;
165 struct gendisk *disk = bdev->bd_disk;
166 struct bio_integrity_payload *bip;
167 struct nd_blk_device *blk_dev;
168 struct bvec_iter iter;
169 unsigned long start;
170 struct bio_vec bvec;
171 int err = 0, rw;
172 bool do_acct;
173
174 /*
175 * bio_integrity_enabled also checks if the bio already has an
176 * integrity payload attached. If it does, we *don't* do a
177 * bio_integrity_prep here - the payload has been generated by
178 * another kernel subsystem, and we just pass it through.
179 */
180 if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
181 bio->bi_error = -EIO;
182 goto out;
183 }
184
185 bip = bio_integrity(bio);
186 blk_dev = disk->private_data;
187 rw = bio_data_dir(bio);
188 do_acct = nd_iostat_start(bio, &start);
189 bio_for_each_segment(bvec, bio, iter) {
190 unsigned int len = bvec.bv_len;
191
192 BUG_ON(len > PAGE_SIZE);
193 err = nd_blk_do_bvec(blk_dev, bip, bvec.bv_page, len,
194 bvec.bv_offset, rw, iter.bi_sector);
195 if (err) {
196 dev_info(&blk_dev->nsblk->common.dev,
197 "io error in %s sector %lld, len %d,\n",
198 (rw == READ) ? "READ" : "WRITE",
199 (unsigned long long) iter.bi_sector, len);
200 bio->bi_error = err;
201 break;
202 }
203 }
204 if (do_acct)
205 nd_iostat_end(bio, start);
206
207 out:
208 bio_endio(bio);
209 return BLK_QC_T_NONE;
210}
211
212static int nd_blk_rw_bytes(struct nd_namespace_common *ndns,
213 resource_size_t offset, void *iobuf, size_t n, int rw)
214{
215 struct nd_blk_device *blk_dev = dev_get_drvdata(ndns->claim);
216 struct nd_namespace_blk *nsblk = blk_dev->nsblk;
217 struct nd_blk_region *ndbr = blk_dev->ndbr;
218 resource_size_t dev_offset;
219
220 dev_offset = to_dev_offset(nsblk, offset, n);
221
222 if (unlikely(offset + n > blk_dev->disk_size)) {
223 dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
224 return -EFAULT;
225 }
226
227 if (dev_offset == SIZE_MAX)
228 return -EIO;
229
230 return ndbr->do_io(ndbr, dev_offset, iobuf, n, rw);
231}
232
233static const struct block_device_operations nd_blk_fops = {
234 .owner = THIS_MODULE,
235 .revalidate_disk = nvdimm_revalidate_disk,
236};
237
238static int nd_blk_attach_disk(struct nd_namespace_common *ndns,
239 struct nd_blk_device *blk_dev)
240{
241 resource_size_t available_disk_size;
242 struct gendisk *disk;
243 u64 internal_nlba;
244
245 internal_nlba = div_u64(blk_dev->disk_size, blk_dev->internal_lbasize);
246 available_disk_size = internal_nlba * blk_dev->sector_size;
247
248 blk_dev->queue = blk_alloc_queue(GFP_KERNEL);
249 if (!blk_dev->queue)
250 return -ENOMEM;
251
252 blk_queue_make_request(blk_dev->queue, nd_blk_make_request);
253 blk_queue_max_hw_sectors(blk_dev->queue, UINT_MAX);
254 blk_queue_bounce_limit(blk_dev->queue, BLK_BOUNCE_ANY);
255 blk_queue_logical_block_size(blk_dev->queue, blk_dev->sector_size);
256 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, blk_dev->queue);
257
258 disk = blk_dev->disk = alloc_disk(0);
259 if (!disk) {
260 blk_cleanup_queue(blk_dev->queue);
261 return -ENOMEM;
262 }
263
264 disk->driverfs_dev = &ndns->dev;
265 disk->first_minor = 0;
266 disk->fops = &nd_blk_fops;
267 disk->private_data = blk_dev;
268 disk->queue = blk_dev->queue;
269 disk->flags = GENHD_FL_EXT_DEVT;
270 nvdimm_namespace_disk_name(ndns, disk->disk_name);
271 set_capacity(disk, 0);
272 add_disk(disk);
273
274 if (nd_blk_meta_size(blk_dev)) {
275 int rc = nd_integrity_init(disk, nd_blk_meta_size(blk_dev));
276
277 if (rc) {
278 del_gendisk(disk);
279 put_disk(disk);
280 blk_cleanup_queue(blk_dev->queue);
281 return rc;
282 }
283 }
284
285 set_capacity(disk, available_disk_size >> SECTOR_SHIFT);
286 revalidate_disk(disk);
287 return 0;
288}
289
290static int nd_blk_probe(struct device *dev)
291{
292 struct nd_namespace_common *ndns;
293 struct nd_namespace_blk *nsblk;
294 struct nd_blk_device *blk_dev;
295 int rc;
296
297 ndns = nvdimm_namespace_common_probe(dev);
298 if (IS_ERR(ndns))
299 return PTR_ERR(ndns);
300
301 blk_dev = kzalloc(sizeof(*blk_dev), GFP_KERNEL);
302 if (!blk_dev)
303 return -ENOMEM;
304
305 nsblk = to_nd_namespace_blk(&ndns->dev);
306 blk_dev->disk_size = nvdimm_namespace_capacity(ndns);
307 blk_dev->ndbr = to_nd_blk_region(dev->parent);
308 blk_dev->nsblk = to_nd_namespace_blk(&ndns->dev);
309 blk_dev->internal_lbasize = roundup(nsblk->lbasize,
310 INT_LBASIZE_ALIGNMENT);
311 blk_dev->sector_size = ((nsblk->lbasize >= 4096) ? 4096 : 512);
312 dev_set_drvdata(dev, blk_dev);
313
314 ndns->rw_bytes = nd_blk_rw_bytes;
315 if (is_nd_btt(dev))
316 rc = nvdimm_namespace_attach_btt(ndns);
317 else if (nd_btt_probe(ndns, blk_dev) == 0) {
318 /* we'll come back as btt-blk */
319 rc = -ENXIO;
320 } else
321 rc = nd_blk_attach_disk(ndns, blk_dev);
322 if (rc)
323 kfree(blk_dev);
324 return rc;
325}
326
327static void nd_blk_detach_disk(struct nd_blk_device *blk_dev)
328{
329 del_gendisk(blk_dev->disk);
330 put_disk(blk_dev->disk);
331 blk_cleanup_queue(blk_dev->queue);
332}
333
334static int nd_blk_remove(struct device *dev)
335{
336 struct nd_blk_device *blk_dev = dev_get_drvdata(dev);
337
338 if (is_nd_btt(dev))
339 nvdimm_namespace_detach_btt(to_nd_btt(dev)->ndns);
340 else
341 nd_blk_detach_disk(blk_dev);
342 kfree(blk_dev);
343
344 return 0;
345}
346
347static struct nd_device_driver nd_blk_driver = {
348 .probe = nd_blk_probe,
349 .remove = nd_blk_remove,
350 .drv = {
351 .name = "nd_blk",
352 },
353 .type = ND_DRIVER_NAMESPACE_BLK,
354};
355
356static int __init nd_blk_init(void)
357{
358 return nd_driver_register(&nd_blk_driver);
359}
360
361static void __exit nd_blk_exit(void)
362{
363 driver_unregister(&nd_blk_driver.drv);
364}
365
366MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
367MODULE_LICENSE("GPL v2");
368MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_BLK);
369module_init(nd_blk_init);
370module_exit(nd_blk_exit);