Loading...
1/*
2 * blk-integrity.c - Block layer data integrity extensions
3 *
4 * Copyright (C) 2007, 2008 Oracle Corporation
5 * Written by: Martin K. Petersen <martin.petersen@oracle.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; see the file COPYING. If not, write to
18 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
19 * USA.
20 *
21 */
22
23#include <linux/blkdev.h>
24#include <linux/backing-dev.h>
25#include <linux/mempool.h>
26#include <linux/bio.h>
27#include <linux/scatterlist.h>
28#include <linux/export.h>
29#include <linux/slab.h>
30
31#include "blk.h"
32
33/**
34 * blk_rq_count_integrity_sg - Count number of integrity scatterlist elements
35 * @q: request queue
36 * @bio: bio with integrity metadata attached
37 *
38 * Description: Returns the number of elements required in a
39 * scatterlist corresponding to the integrity metadata in a bio.
40 */
41int blk_rq_count_integrity_sg(struct request_queue *q, struct bio *bio)
42{
43 struct bio_vec iv, ivprv = { NULL };
44 unsigned int segments = 0;
45 unsigned int seg_size = 0;
46 struct bvec_iter iter;
47 int prev = 0;
48
49 bio_for_each_integrity_vec(iv, bio, iter) {
50
51 if (prev) {
52 if (!BIOVEC_PHYS_MERGEABLE(&ivprv, &iv))
53 goto new_segment;
54
55 if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv))
56 goto new_segment;
57
58 if (seg_size + iv.bv_len > queue_max_segment_size(q))
59 goto new_segment;
60
61 seg_size += iv.bv_len;
62 } else {
63new_segment:
64 segments++;
65 seg_size = iv.bv_len;
66 }
67
68 prev = 1;
69 ivprv = iv;
70 }
71
72 return segments;
73}
74EXPORT_SYMBOL(blk_rq_count_integrity_sg);
75
76/**
77 * blk_rq_map_integrity_sg - Map integrity metadata into a scatterlist
78 * @q: request queue
79 * @bio: bio with integrity metadata attached
80 * @sglist: target scatterlist
81 *
82 * Description: Map the integrity vectors in request into a
83 * scatterlist. The scatterlist must be big enough to hold all
84 * elements. I.e. sized using blk_rq_count_integrity_sg().
85 */
86int blk_rq_map_integrity_sg(struct request_queue *q, struct bio *bio,
87 struct scatterlist *sglist)
88{
89 struct bio_vec iv, ivprv = { NULL };
90 struct scatterlist *sg = NULL;
91 unsigned int segments = 0;
92 struct bvec_iter iter;
93 int prev = 0;
94
95 bio_for_each_integrity_vec(iv, bio, iter) {
96
97 if (prev) {
98 if (!BIOVEC_PHYS_MERGEABLE(&ivprv, &iv))
99 goto new_segment;
100
101 if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv))
102 goto new_segment;
103
104 if (sg->length + iv.bv_len > queue_max_segment_size(q))
105 goto new_segment;
106
107 sg->length += iv.bv_len;
108 } else {
109new_segment:
110 if (!sg)
111 sg = sglist;
112 else {
113 sg_unmark_end(sg);
114 sg = sg_next(sg);
115 }
116
117 sg_set_page(sg, iv.bv_page, iv.bv_len, iv.bv_offset);
118 segments++;
119 }
120
121 prev = 1;
122 ivprv = iv;
123 }
124
125 if (sg)
126 sg_mark_end(sg);
127
128 return segments;
129}
130EXPORT_SYMBOL(blk_rq_map_integrity_sg);
131
132/**
133 * blk_integrity_compare - Compare integrity profile of two disks
134 * @gd1: Disk to compare
135 * @gd2: Disk to compare
136 *
137 * Description: Meta-devices like DM and MD need to verify that all
138 * sub-devices use the same integrity format before advertising to
139 * upper layers that they can send/receive integrity metadata. This
140 * function can be used to check whether two gendisk devices have
141 * compatible integrity formats.
142 */
143int blk_integrity_compare(struct gendisk *gd1, struct gendisk *gd2)
144{
145 struct blk_integrity *b1 = &gd1->queue->integrity;
146 struct blk_integrity *b2 = &gd2->queue->integrity;
147
148 if (!b1->profile && !b2->profile)
149 return 0;
150
151 if (!b1->profile || !b2->profile)
152 return -1;
153
154 if (b1->interval_exp != b2->interval_exp) {
155 pr_err("%s: %s/%s protection interval %u != %u\n",
156 __func__, gd1->disk_name, gd2->disk_name,
157 1 << b1->interval_exp, 1 << b2->interval_exp);
158 return -1;
159 }
160
161 if (b1->tuple_size != b2->tuple_size) {
162 pr_err("%s: %s/%s tuple sz %u != %u\n", __func__,
163 gd1->disk_name, gd2->disk_name,
164 b1->tuple_size, b2->tuple_size);
165 return -1;
166 }
167
168 if (b1->tag_size && b2->tag_size && (b1->tag_size != b2->tag_size)) {
169 pr_err("%s: %s/%s tag sz %u != %u\n", __func__,
170 gd1->disk_name, gd2->disk_name,
171 b1->tag_size, b2->tag_size);
172 return -1;
173 }
174
175 if (b1->profile != b2->profile) {
176 pr_err("%s: %s/%s type %s != %s\n", __func__,
177 gd1->disk_name, gd2->disk_name,
178 b1->profile->name, b2->profile->name);
179 return -1;
180 }
181
182 return 0;
183}
184EXPORT_SYMBOL(blk_integrity_compare);
185
186bool blk_integrity_merge_rq(struct request_queue *q, struct request *req,
187 struct request *next)
188{
189 if (blk_integrity_rq(req) == 0 && blk_integrity_rq(next) == 0)
190 return true;
191
192 if (blk_integrity_rq(req) == 0 || blk_integrity_rq(next) == 0)
193 return false;
194
195 if (bio_integrity(req->bio)->bip_flags !=
196 bio_integrity(next->bio)->bip_flags)
197 return false;
198
199 if (req->nr_integrity_segments + next->nr_integrity_segments >
200 q->limits.max_integrity_segments)
201 return false;
202
203 if (integrity_req_gap_back_merge(req, next->bio))
204 return false;
205
206 return true;
207}
208EXPORT_SYMBOL(blk_integrity_merge_rq);
209
210bool blk_integrity_merge_bio(struct request_queue *q, struct request *req,
211 struct bio *bio)
212{
213 int nr_integrity_segs;
214 struct bio *next = bio->bi_next;
215
216 if (blk_integrity_rq(req) == 0 && bio_integrity(bio) == NULL)
217 return true;
218
219 if (blk_integrity_rq(req) == 0 || bio_integrity(bio) == NULL)
220 return false;
221
222 if (bio_integrity(req->bio)->bip_flags != bio_integrity(bio)->bip_flags)
223 return false;
224
225 bio->bi_next = NULL;
226 nr_integrity_segs = blk_rq_count_integrity_sg(q, bio);
227 bio->bi_next = next;
228
229 if (req->nr_integrity_segments + nr_integrity_segs >
230 q->limits.max_integrity_segments)
231 return false;
232
233 req->nr_integrity_segments += nr_integrity_segs;
234
235 return true;
236}
237EXPORT_SYMBOL(blk_integrity_merge_bio);
238
239struct integrity_sysfs_entry {
240 struct attribute attr;
241 ssize_t (*show)(struct blk_integrity *, char *);
242 ssize_t (*store)(struct blk_integrity *, const char *, size_t);
243};
244
245static ssize_t integrity_attr_show(struct kobject *kobj, struct attribute *attr,
246 char *page)
247{
248 struct gendisk *disk = container_of(kobj, struct gendisk, integrity_kobj);
249 struct blk_integrity *bi = &disk->queue->integrity;
250 struct integrity_sysfs_entry *entry =
251 container_of(attr, struct integrity_sysfs_entry, attr);
252
253 return entry->show(bi, page);
254}
255
256static ssize_t integrity_attr_store(struct kobject *kobj,
257 struct attribute *attr, const char *page,
258 size_t count)
259{
260 struct gendisk *disk = container_of(kobj, struct gendisk, integrity_kobj);
261 struct blk_integrity *bi = &disk->queue->integrity;
262 struct integrity_sysfs_entry *entry =
263 container_of(attr, struct integrity_sysfs_entry, attr);
264 ssize_t ret = 0;
265
266 if (entry->store)
267 ret = entry->store(bi, page, count);
268
269 return ret;
270}
271
272static ssize_t integrity_format_show(struct blk_integrity *bi, char *page)
273{
274 if (bi->profile && bi->profile->name)
275 return sprintf(page, "%s\n", bi->profile->name);
276 else
277 return sprintf(page, "none\n");
278}
279
280static ssize_t integrity_tag_size_show(struct blk_integrity *bi, char *page)
281{
282 return sprintf(page, "%u\n", bi->tag_size);
283}
284
285static ssize_t integrity_interval_show(struct blk_integrity *bi, char *page)
286{
287 return sprintf(page, "%u\n",
288 bi->interval_exp ? 1 << bi->interval_exp : 0);
289}
290
291static ssize_t integrity_verify_store(struct blk_integrity *bi,
292 const char *page, size_t count)
293{
294 char *p = (char *) page;
295 unsigned long val = simple_strtoul(p, &p, 10);
296
297 if (val)
298 bi->flags |= BLK_INTEGRITY_VERIFY;
299 else
300 bi->flags &= ~BLK_INTEGRITY_VERIFY;
301
302 return count;
303}
304
305static ssize_t integrity_verify_show(struct blk_integrity *bi, char *page)
306{
307 return sprintf(page, "%d\n", (bi->flags & BLK_INTEGRITY_VERIFY) != 0);
308}
309
310static ssize_t integrity_generate_store(struct blk_integrity *bi,
311 const char *page, size_t count)
312{
313 char *p = (char *) page;
314 unsigned long val = simple_strtoul(p, &p, 10);
315
316 if (val)
317 bi->flags |= BLK_INTEGRITY_GENERATE;
318 else
319 bi->flags &= ~BLK_INTEGRITY_GENERATE;
320
321 return count;
322}
323
324static ssize_t integrity_generate_show(struct blk_integrity *bi, char *page)
325{
326 return sprintf(page, "%d\n", (bi->flags & BLK_INTEGRITY_GENERATE) != 0);
327}
328
329static ssize_t integrity_device_show(struct blk_integrity *bi, char *page)
330{
331 return sprintf(page, "%u\n",
332 (bi->flags & BLK_INTEGRITY_DEVICE_CAPABLE) != 0);
333}
334
335static struct integrity_sysfs_entry integrity_format_entry = {
336 .attr = { .name = "format", .mode = S_IRUGO },
337 .show = integrity_format_show,
338};
339
340static struct integrity_sysfs_entry integrity_tag_size_entry = {
341 .attr = { .name = "tag_size", .mode = S_IRUGO },
342 .show = integrity_tag_size_show,
343};
344
345static struct integrity_sysfs_entry integrity_interval_entry = {
346 .attr = { .name = "protection_interval_bytes", .mode = S_IRUGO },
347 .show = integrity_interval_show,
348};
349
350static struct integrity_sysfs_entry integrity_verify_entry = {
351 .attr = { .name = "read_verify", .mode = S_IRUGO | S_IWUSR },
352 .show = integrity_verify_show,
353 .store = integrity_verify_store,
354};
355
356static struct integrity_sysfs_entry integrity_generate_entry = {
357 .attr = { .name = "write_generate", .mode = S_IRUGO | S_IWUSR },
358 .show = integrity_generate_show,
359 .store = integrity_generate_store,
360};
361
362static struct integrity_sysfs_entry integrity_device_entry = {
363 .attr = { .name = "device_is_integrity_capable", .mode = S_IRUGO },
364 .show = integrity_device_show,
365};
366
367static struct attribute *integrity_attrs[] = {
368 &integrity_format_entry.attr,
369 &integrity_tag_size_entry.attr,
370 &integrity_interval_entry.attr,
371 &integrity_verify_entry.attr,
372 &integrity_generate_entry.attr,
373 &integrity_device_entry.attr,
374 NULL,
375};
376
377static const struct sysfs_ops integrity_ops = {
378 .show = &integrity_attr_show,
379 .store = &integrity_attr_store,
380};
381
382static struct kobj_type integrity_ktype = {
383 .default_attrs = integrity_attrs,
384 .sysfs_ops = &integrity_ops,
385};
386
387static blk_status_t blk_integrity_nop_fn(struct blk_integrity_iter *iter)
388{
389 return BLK_STS_OK;
390}
391
392static const struct blk_integrity_profile nop_profile = {
393 .name = "nop",
394 .generate_fn = blk_integrity_nop_fn,
395 .verify_fn = blk_integrity_nop_fn,
396};
397
398/**
399 * blk_integrity_register - Register a gendisk as being integrity-capable
400 * @disk: struct gendisk pointer to make integrity-aware
401 * @template: block integrity profile to register
402 *
403 * Description: When a device needs to advertise itself as being able to
404 * send/receive integrity metadata it must use this function to register
405 * the capability with the block layer. The template is a blk_integrity
406 * struct with values appropriate for the underlying hardware. See
407 * Documentation/block/data-integrity.txt.
408 */
409void blk_integrity_register(struct gendisk *disk, struct blk_integrity *template)
410{
411 struct blk_integrity *bi = &disk->queue->integrity;
412
413 bi->flags = BLK_INTEGRITY_VERIFY | BLK_INTEGRITY_GENERATE |
414 template->flags;
415 bi->interval_exp = template->interval_exp ? :
416 ilog2(queue_logical_block_size(disk->queue));
417 bi->profile = template->profile ? template->profile : &nop_profile;
418 bi->tuple_size = template->tuple_size;
419 bi->tag_size = template->tag_size;
420
421 disk->queue->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES;
422}
423EXPORT_SYMBOL(blk_integrity_register);
424
425/**
426 * blk_integrity_unregister - Unregister block integrity profile
427 * @disk: disk whose integrity profile to unregister
428 *
429 * Description: This function unregisters the integrity capability from
430 * a block device.
431 */
432void blk_integrity_unregister(struct gendisk *disk)
433{
434 disk->queue->backing_dev_info->capabilities &= ~BDI_CAP_STABLE_WRITES;
435 memset(&disk->queue->integrity, 0, sizeof(struct blk_integrity));
436}
437EXPORT_SYMBOL(blk_integrity_unregister);
438
439void blk_integrity_add(struct gendisk *disk)
440{
441 if (kobject_init_and_add(&disk->integrity_kobj, &integrity_ktype,
442 &disk_to_dev(disk)->kobj, "%s", "integrity"))
443 return;
444
445 kobject_uevent(&disk->integrity_kobj, KOBJ_ADD);
446}
447
448void blk_integrity_del(struct gendisk *disk)
449{
450 kobject_uevent(&disk->integrity_kobj, KOBJ_REMOVE);
451 kobject_del(&disk->integrity_kobj);
452 kobject_put(&disk->integrity_kobj);
453}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * blk-integrity.c - Block layer data integrity extensions
4 *
5 * Copyright (C) 2007, 2008 Oracle Corporation
6 * Written by: Martin K. Petersen <martin.petersen@oracle.com>
7 */
8
9#include <linux/blkdev.h>
10#include <linux/backing-dev.h>
11#include <linux/mempool.h>
12#include <linux/bio.h>
13#include <linux/scatterlist.h>
14#include <linux/export.h>
15#include <linux/slab.h>
16
17#include "blk.h"
18
19/**
20 * blk_rq_count_integrity_sg - Count number of integrity scatterlist elements
21 * @q: request queue
22 * @bio: bio with integrity metadata attached
23 *
24 * Description: Returns the number of elements required in a
25 * scatterlist corresponding to the integrity metadata in a bio.
26 */
27int blk_rq_count_integrity_sg(struct request_queue *q, struct bio *bio)
28{
29 struct bio_vec iv, ivprv = { NULL };
30 unsigned int segments = 0;
31 unsigned int seg_size = 0;
32 struct bvec_iter iter;
33 int prev = 0;
34
35 bio_for_each_integrity_vec(iv, bio, iter) {
36
37 if (prev) {
38 if (!biovec_phys_mergeable(q, &ivprv, &iv))
39 goto new_segment;
40 if (seg_size + iv.bv_len > queue_max_segment_size(q))
41 goto new_segment;
42
43 seg_size += iv.bv_len;
44 } else {
45new_segment:
46 segments++;
47 seg_size = iv.bv_len;
48 }
49
50 prev = 1;
51 ivprv = iv;
52 }
53
54 return segments;
55}
56EXPORT_SYMBOL(blk_rq_count_integrity_sg);
57
58/**
59 * blk_rq_map_integrity_sg - Map integrity metadata into a scatterlist
60 * @q: request queue
61 * @bio: bio with integrity metadata attached
62 * @sglist: target scatterlist
63 *
64 * Description: Map the integrity vectors in request into a
65 * scatterlist. The scatterlist must be big enough to hold all
66 * elements. I.e. sized using blk_rq_count_integrity_sg().
67 */
68int blk_rq_map_integrity_sg(struct request_queue *q, struct bio *bio,
69 struct scatterlist *sglist)
70{
71 struct bio_vec iv, ivprv = { NULL };
72 struct scatterlist *sg = NULL;
73 unsigned int segments = 0;
74 struct bvec_iter iter;
75 int prev = 0;
76
77 bio_for_each_integrity_vec(iv, bio, iter) {
78
79 if (prev) {
80 if (!biovec_phys_mergeable(q, &ivprv, &iv))
81 goto new_segment;
82 if (sg->length + iv.bv_len > queue_max_segment_size(q))
83 goto new_segment;
84
85 sg->length += iv.bv_len;
86 } else {
87new_segment:
88 if (!sg)
89 sg = sglist;
90 else {
91 sg_unmark_end(sg);
92 sg = sg_next(sg);
93 }
94
95 sg_set_page(sg, iv.bv_page, iv.bv_len, iv.bv_offset);
96 segments++;
97 }
98
99 prev = 1;
100 ivprv = iv;
101 }
102
103 if (sg)
104 sg_mark_end(sg);
105
106 return segments;
107}
108EXPORT_SYMBOL(blk_rq_map_integrity_sg);
109
110/**
111 * blk_integrity_compare - Compare integrity profile of two disks
112 * @gd1: Disk to compare
113 * @gd2: Disk to compare
114 *
115 * Description: Meta-devices like DM and MD need to verify that all
116 * sub-devices use the same integrity format before advertising to
117 * upper layers that they can send/receive integrity metadata. This
118 * function can be used to check whether two gendisk devices have
119 * compatible integrity formats.
120 */
121int blk_integrity_compare(struct gendisk *gd1, struct gendisk *gd2)
122{
123 struct blk_integrity *b1 = &gd1->queue->integrity;
124 struct blk_integrity *b2 = &gd2->queue->integrity;
125
126 if (!b1->profile && !b2->profile)
127 return 0;
128
129 if (!b1->profile || !b2->profile)
130 return -1;
131
132 if (b1->interval_exp != b2->interval_exp) {
133 pr_err("%s: %s/%s protection interval %u != %u\n",
134 __func__, gd1->disk_name, gd2->disk_name,
135 1 << b1->interval_exp, 1 << b2->interval_exp);
136 return -1;
137 }
138
139 if (b1->tuple_size != b2->tuple_size) {
140 pr_err("%s: %s/%s tuple sz %u != %u\n", __func__,
141 gd1->disk_name, gd2->disk_name,
142 b1->tuple_size, b2->tuple_size);
143 return -1;
144 }
145
146 if (b1->tag_size && b2->tag_size && (b1->tag_size != b2->tag_size)) {
147 pr_err("%s: %s/%s tag sz %u != %u\n", __func__,
148 gd1->disk_name, gd2->disk_name,
149 b1->tag_size, b2->tag_size);
150 return -1;
151 }
152
153 if (b1->profile != b2->profile) {
154 pr_err("%s: %s/%s type %s != %s\n", __func__,
155 gd1->disk_name, gd2->disk_name,
156 b1->profile->name, b2->profile->name);
157 return -1;
158 }
159
160 return 0;
161}
162EXPORT_SYMBOL(blk_integrity_compare);
163
164bool blk_integrity_merge_rq(struct request_queue *q, struct request *req,
165 struct request *next)
166{
167 if (blk_integrity_rq(req) == 0 && blk_integrity_rq(next) == 0)
168 return true;
169
170 if (blk_integrity_rq(req) == 0 || blk_integrity_rq(next) == 0)
171 return false;
172
173 if (bio_integrity(req->bio)->bip_flags !=
174 bio_integrity(next->bio)->bip_flags)
175 return false;
176
177 if (req->nr_integrity_segments + next->nr_integrity_segments >
178 q->limits.max_integrity_segments)
179 return false;
180
181 if (integrity_req_gap_back_merge(req, next->bio))
182 return false;
183
184 return true;
185}
186EXPORT_SYMBOL(blk_integrity_merge_rq);
187
188bool blk_integrity_merge_bio(struct request_queue *q, struct request *req,
189 struct bio *bio)
190{
191 int nr_integrity_segs;
192 struct bio *next = bio->bi_next;
193
194 if (blk_integrity_rq(req) == 0 && bio_integrity(bio) == NULL)
195 return true;
196
197 if (blk_integrity_rq(req) == 0 || bio_integrity(bio) == NULL)
198 return false;
199
200 if (bio_integrity(req->bio)->bip_flags != bio_integrity(bio)->bip_flags)
201 return false;
202
203 bio->bi_next = NULL;
204 nr_integrity_segs = blk_rq_count_integrity_sg(q, bio);
205 bio->bi_next = next;
206
207 if (req->nr_integrity_segments + nr_integrity_segs >
208 q->limits.max_integrity_segments)
209 return false;
210
211 req->nr_integrity_segments += nr_integrity_segs;
212
213 return true;
214}
215EXPORT_SYMBOL(blk_integrity_merge_bio);
216
217struct integrity_sysfs_entry {
218 struct attribute attr;
219 ssize_t (*show)(struct blk_integrity *, char *);
220 ssize_t (*store)(struct blk_integrity *, const char *, size_t);
221};
222
223static ssize_t integrity_attr_show(struct kobject *kobj, struct attribute *attr,
224 char *page)
225{
226 struct gendisk *disk = container_of(kobj, struct gendisk, integrity_kobj);
227 struct blk_integrity *bi = &disk->queue->integrity;
228 struct integrity_sysfs_entry *entry =
229 container_of(attr, struct integrity_sysfs_entry, attr);
230
231 return entry->show(bi, page);
232}
233
234static ssize_t integrity_attr_store(struct kobject *kobj,
235 struct attribute *attr, const char *page,
236 size_t count)
237{
238 struct gendisk *disk = container_of(kobj, struct gendisk, integrity_kobj);
239 struct blk_integrity *bi = &disk->queue->integrity;
240 struct integrity_sysfs_entry *entry =
241 container_of(attr, struct integrity_sysfs_entry, attr);
242 ssize_t ret = 0;
243
244 if (entry->store)
245 ret = entry->store(bi, page, count);
246
247 return ret;
248}
249
250static ssize_t integrity_format_show(struct blk_integrity *bi, char *page)
251{
252 if (bi->profile && bi->profile->name)
253 return sprintf(page, "%s\n", bi->profile->name);
254 else
255 return sprintf(page, "none\n");
256}
257
258static ssize_t integrity_tag_size_show(struct blk_integrity *bi, char *page)
259{
260 return sprintf(page, "%u\n", bi->tag_size);
261}
262
263static ssize_t integrity_interval_show(struct blk_integrity *bi, char *page)
264{
265 return sprintf(page, "%u\n",
266 bi->interval_exp ? 1 << bi->interval_exp : 0);
267}
268
269static ssize_t integrity_verify_store(struct blk_integrity *bi,
270 const char *page, size_t count)
271{
272 char *p = (char *) page;
273 unsigned long val = simple_strtoul(p, &p, 10);
274
275 if (val)
276 bi->flags |= BLK_INTEGRITY_VERIFY;
277 else
278 bi->flags &= ~BLK_INTEGRITY_VERIFY;
279
280 return count;
281}
282
283static ssize_t integrity_verify_show(struct blk_integrity *bi, char *page)
284{
285 return sprintf(page, "%d\n", (bi->flags & BLK_INTEGRITY_VERIFY) != 0);
286}
287
288static ssize_t integrity_generate_store(struct blk_integrity *bi,
289 const char *page, size_t count)
290{
291 char *p = (char *) page;
292 unsigned long val = simple_strtoul(p, &p, 10);
293
294 if (val)
295 bi->flags |= BLK_INTEGRITY_GENERATE;
296 else
297 bi->flags &= ~BLK_INTEGRITY_GENERATE;
298
299 return count;
300}
301
302static ssize_t integrity_generate_show(struct blk_integrity *bi, char *page)
303{
304 return sprintf(page, "%d\n", (bi->flags & BLK_INTEGRITY_GENERATE) != 0);
305}
306
307static ssize_t integrity_device_show(struct blk_integrity *bi, char *page)
308{
309 return sprintf(page, "%u\n",
310 (bi->flags & BLK_INTEGRITY_DEVICE_CAPABLE) != 0);
311}
312
313static struct integrity_sysfs_entry integrity_format_entry = {
314 .attr = { .name = "format", .mode = 0444 },
315 .show = integrity_format_show,
316};
317
318static struct integrity_sysfs_entry integrity_tag_size_entry = {
319 .attr = { .name = "tag_size", .mode = 0444 },
320 .show = integrity_tag_size_show,
321};
322
323static struct integrity_sysfs_entry integrity_interval_entry = {
324 .attr = { .name = "protection_interval_bytes", .mode = 0444 },
325 .show = integrity_interval_show,
326};
327
328static struct integrity_sysfs_entry integrity_verify_entry = {
329 .attr = { .name = "read_verify", .mode = 0644 },
330 .show = integrity_verify_show,
331 .store = integrity_verify_store,
332};
333
334static struct integrity_sysfs_entry integrity_generate_entry = {
335 .attr = { .name = "write_generate", .mode = 0644 },
336 .show = integrity_generate_show,
337 .store = integrity_generate_store,
338};
339
340static struct integrity_sysfs_entry integrity_device_entry = {
341 .attr = { .name = "device_is_integrity_capable", .mode = 0444 },
342 .show = integrity_device_show,
343};
344
345static struct attribute *integrity_attrs[] = {
346 &integrity_format_entry.attr,
347 &integrity_tag_size_entry.attr,
348 &integrity_interval_entry.attr,
349 &integrity_verify_entry.attr,
350 &integrity_generate_entry.attr,
351 &integrity_device_entry.attr,
352 NULL,
353};
354ATTRIBUTE_GROUPS(integrity);
355
356static const struct sysfs_ops integrity_ops = {
357 .show = &integrity_attr_show,
358 .store = &integrity_attr_store,
359};
360
361static struct kobj_type integrity_ktype = {
362 .default_groups = integrity_groups,
363 .sysfs_ops = &integrity_ops,
364};
365
366static blk_status_t blk_integrity_nop_fn(struct blk_integrity_iter *iter)
367{
368 return BLK_STS_OK;
369}
370
371static void blk_integrity_nop_prepare(struct request *rq)
372{
373}
374
375static void blk_integrity_nop_complete(struct request *rq,
376 unsigned int nr_bytes)
377{
378}
379
380static const struct blk_integrity_profile nop_profile = {
381 .name = "nop",
382 .generate_fn = blk_integrity_nop_fn,
383 .verify_fn = blk_integrity_nop_fn,
384 .prepare_fn = blk_integrity_nop_prepare,
385 .complete_fn = blk_integrity_nop_complete,
386};
387
388/**
389 * blk_integrity_register - Register a gendisk as being integrity-capable
390 * @disk: struct gendisk pointer to make integrity-aware
391 * @template: block integrity profile to register
392 *
393 * Description: When a device needs to advertise itself as being able to
394 * send/receive integrity metadata it must use this function to register
395 * the capability with the block layer. The template is a blk_integrity
396 * struct with values appropriate for the underlying hardware. See
397 * Documentation/block/data-integrity.rst.
398 */
399void blk_integrity_register(struct gendisk *disk, struct blk_integrity *template)
400{
401 struct blk_integrity *bi = &disk->queue->integrity;
402
403 bi->flags = BLK_INTEGRITY_VERIFY | BLK_INTEGRITY_GENERATE |
404 template->flags;
405 bi->interval_exp = template->interval_exp ? :
406 ilog2(queue_logical_block_size(disk->queue));
407 bi->profile = template->profile ? template->profile : &nop_profile;
408 bi->tuple_size = template->tuple_size;
409 bi->tag_size = template->tag_size;
410
411 disk->queue->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES;
412}
413EXPORT_SYMBOL(blk_integrity_register);
414
415/**
416 * blk_integrity_unregister - Unregister block integrity profile
417 * @disk: disk whose integrity profile to unregister
418 *
419 * Description: This function unregisters the integrity capability from
420 * a block device.
421 */
422void blk_integrity_unregister(struct gendisk *disk)
423{
424 disk->queue->backing_dev_info->capabilities &= ~BDI_CAP_STABLE_WRITES;
425 memset(&disk->queue->integrity, 0, sizeof(struct blk_integrity));
426}
427EXPORT_SYMBOL(blk_integrity_unregister);
428
429void blk_integrity_add(struct gendisk *disk)
430{
431 if (kobject_init_and_add(&disk->integrity_kobj, &integrity_ktype,
432 &disk_to_dev(disk)->kobj, "%s", "integrity"))
433 return;
434
435 kobject_uevent(&disk->integrity_kobj, KOBJ_ADD);
436}
437
438void blk_integrity_del(struct gendisk *disk)
439{
440 kobject_uevent(&disk->integrity_kobj, KOBJ_REMOVE);
441 kobject_del(&disk->integrity_kobj);
442 kobject_put(&disk->integrity_kobj);
443}