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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/mempool.h>
25#include <linux/bio.h>
26#include <linux/scatterlist.h>
27#include <linux/export.h>
28#include <linux/slab.h>
29
30#include "blk.h"
31
32static struct kmem_cache *integrity_cachep;
33
34static const char *bi_unsupported_name = "unsupported";
35
36/**
37 * blk_rq_count_integrity_sg - Count number of integrity scatterlist elements
38 * @q: request queue
39 * @bio: bio with integrity metadata attached
40 *
41 * Description: Returns the number of elements required in a
42 * scatterlist corresponding to the integrity metadata in a bio.
43 */
44int blk_rq_count_integrity_sg(struct request_queue *q, struct bio *bio)
45{
46 struct bio_vec *iv, *ivprv = NULL;
47 unsigned int segments = 0;
48 unsigned int seg_size = 0;
49 unsigned int i = 0;
50
51 bio_for_each_integrity_vec(iv, bio, i) {
52
53 if (ivprv) {
54 if (!BIOVEC_PHYS_MERGEABLE(ivprv, iv))
55 goto new_segment;
56
57 if (!BIOVEC_SEG_BOUNDARY(q, ivprv, iv))
58 goto new_segment;
59
60 if (seg_size + iv->bv_len > queue_max_segment_size(q))
61 goto new_segment;
62
63 seg_size += iv->bv_len;
64 } else {
65new_segment:
66 segments++;
67 seg_size = iv->bv_len;
68 }
69
70 ivprv = iv;
71 }
72
73 return segments;
74}
75EXPORT_SYMBOL(blk_rq_count_integrity_sg);
76
77/**
78 * blk_rq_map_integrity_sg - Map integrity metadata into a scatterlist
79 * @q: request queue
80 * @bio: bio with integrity metadata attached
81 * @sglist: target scatterlist
82 *
83 * Description: Map the integrity vectors in request into a
84 * scatterlist. The scatterlist must be big enough to hold all
85 * elements. I.e. sized using blk_rq_count_integrity_sg().
86 */
87int blk_rq_map_integrity_sg(struct request_queue *q, struct bio *bio,
88 struct scatterlist *sglist)
89{
90 struct bio_vec *iv, *ivprv = NULL;
91 struct scatterlist *sg = NULL;
92 unsigned int segments = 0;
93 unsigned int i = 0;
94
95 bio_for_each_integrity_vec(iv, bio, i) {
96
97 if (ivprv) {
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->page_link &= ~0x02;
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 ivprv = iv;
122 }
123
124 if (sg)
125 sg_mark_end(sg);
126
127 return segments;
128}
129EXPORT_SYMBOL(blk_rq_map_integrity_sg);
130
131/**
132 * blk_integrity_compare - Compare integrity profile of two disks
133 * @gd1: Disk to compare
134 * @gd2: Disk to compare
135 *
136 * Description: Meta-devices like DM and MD need to verify that all
137 * sub-devices use the same integrity format before advertising to
138 * upper layers that they can send/receive integrity metadata. This
139 * function can be used to check whether two gendisk devices have
140 * compatible integrity formats.
141 */
142int blk_integrity_compare(struct gendisk *gd1, struct gendisk *gd2)
143{
144 struct blk_integrity *b1 = gd1->integrity;
145 struct blk_integrity *b2 = gd2->integrity;
146
147 if (!b1 && !b2)
148 return 0;
149
150 if (!b1 || !b2)
151 return -1;
152
153 if (b1->sector_size != b2->sector_size) {
154 printk(KERN_ERR "%s: %s/%s sector sz %u != %u\n", __func__,
155 gd1->disk_name, gd2->disk_name,
156 b1->sector_size, b2->sector_size);
157 return -1;
158 }
159
160 if (b1->tuple_size != b2->tuple_size) {
161 printk(KERN_ERR "%s: %s/%s tuple sz %u != %u\n", __func__,
162 gd1->disk_name, gd2->disk_name,
163 b1->tuple_size, b2->tuple_size);
164 return -1;
165 }
166
167 if (b1->tag_size && b2->tag_size && (b1->tag_size != b2->tag_size)) {
168 printk(KERN_ERR "%s: %s/%s tag sz %u != %u\n", __func__,
169 gd1->disk_name, gd2->disk_name,
170 b1->tag_size, b2->tag_size);
171 return -1;
172 }
173
174 if (strcmp(b1->name, b2->name)) {
175 printk(KERN_ERR "%s: %s/%s type %s != %s\n", __func__,
176 gd1->disk_name, gd2->disk_name,
177 b1->name, b2->name);
178 return -1;
179 }
180
181 return 0;
182}
183EXPORT_SYMBOL(blk_integrity_compare);
184
185int blk_integrity_merge_rq(struct request_queue *q, struct request *req,
186 struct request *next)
187{
188 if (blk_integrity_rq(req) != blk_integrity_rq(next))
189 return -1;
190
191 if (req->nr_integrity_segments + next->nr_integrity_segments >
192 q->limits.max_integrity_segments)
193 return -1;
194
195 return 0;
196}
197EXPORT_SYMBOL(blk_integrity_merge_rq);
198
199int blk_integrity_merge_bio(struct request_queue *q, struct request *req,
200 struct bio *bio)
201{
202 int nr_integrity_segs;
203 struct bio *next = bio->bi_next;
204
205 bio->bi_next = NULL;
206 nr_integrity_segs = blk_rq_count_integrity_sg(q, bio);
207 bio->bi_next = next;
208
209 if (req->nr_integrity_segments + nr_integrity_segs >
210 q->limits.max_integrity_segments)
211 return -1;
212
213 req->nr_integrity_segments += nr_integrity_segs;
214
215 return 0;
216}
217EXPORT_SYMBOL(blk_integrity_merge_bio);
218
219struct integrity_sysfs_entry {
220 struct attribute attr;
221 ssize_t (*show)(struct blk_integrity *, char *);
222 ssize_t (*store)(struct blk_integrity *, const char *, size_t);
223};
224
225static ssize_t integrity_attr_show(struct kobject *kobj, struct attribute *attr,
226 char *page)
227{
228 struct blk_integrity *bi =
229 container_of(kobj, struct blk_integrity, kobj);
230 struct integrity_sysfs_entry *entry =
231 container_of(attr, struct integrity_sysfs_entry, attr);
232
233 return entry->show(bi, page);
234}
235
236static ssize_t integrity_attr_store(struct kobject *kobj,
237 struct attribute *attr, const char *page,
238 size_t count)
239{
240 struct blk_integrity *bi =
241 container_of(kobj, struct blk_integrity, kobj);
242 struct integrity_sysfs_entry *entry =
243 container_of(attr, struct integrity_sysfs_entry, attr);
244 ssize_t ret = 0;
245
246 if (entry->store)
247 ret = entry->store(bi, page, count);
248
249 return ret;
250}
251
252static ssize_t integrity_format_show(struct blk_integrity *bi, char *page)
253{
254 if (bi != NULL && bi->name != NULL)
255 return sprintf(page, "%s\n", bi->name);
256 else
257 return sprintf(page, "none\n");
258}
259
260static ssize_t integrity_tag_size_show(struct blk_integrity *bi, char *page)
261{
262 if (bi != NULL)
263 return sprintf(page, "%u\n", bi->tag_size);
264 else
265 return sprintf(page, "0\n");
266}
267
268static ssize_t integrity_read_store(struct blk_integrity *bi,
269 const char *page, size_t count)
270{
271 char *p = (char *) page;
272 unsigned long val = simple_strtoul(p, &p, 10);
273
274 if (val)
275 bi->flags |= INTEGRITY_FLAG_READ;
276 else
277 bi->flags &= ~INTEGRITY_FLAG_READ;
278
279 return count;
280}
281
282static ssize_t integrity_read_show(struct blk_integrity *bi, char *page)
283{
284 return sprintf(page, "%d\n", (bi->flags & INTEGRITY_FLAG_READ) != 0);
285}
286
287static ssize_t integrity_write_store(struct blk_integrity *bi,
288 const char *page, size_t count)
289{
290 char *p = (char *) page;
291 unsigned long val = simple_strtoul(p, &p, 10);
292
293 if (val)
294 bi->flags |= INTEGRITY_FLAG_WRITE;
295 else
296 bi->flags &= ~INTEGRITY_FLAG_WRITE;
297
298 return count;
299}
300
301static ssize_t integrity_write_show(struct blk_integrity *bi, char *page)
302{
303 return sprintf(page, "%d\n", (bi->flags & INTEGRITY_FLAG_WRITE) != 0);
304}
305
306static struct integrity_sysfs_entry integrity_format_entry = {
307 .attr = { .name = "format", .mode = S_IRUGO },
308 .show = integrity_format_show,
309};
310
311static struct integrity_sysfs_entry integrity_tag_size_entry = {
312 .attr = { .name = "tag_size", .mode = S_IRUGO },
313 .show = integrity_tag_size_show,
314};
315
316static struct integrity_sysfs_entry integrity_read_entry = {
317 .attr = { .name = "read_verify", .mode = S_IRUGO | S_IWUSR },
318 .show = integrity_read_show,
319 .store = integrity_read_store,
320};
321
322static struct integrity_sysfs_entry integrity_write_entry = {
323 .attr = { .name = "write_generate", .mode = S_IRUGO | S_IWUSR },
324 .show = integrity_write_show,
325 .store = integrity_write_store,
326};
327
328static struct attribute *integrity_attrs[] = {
329 &integrity_format_entry.attr,
330 &integrity_tag_size_entry.attr,
331 &integrity_read_entry.attr,
332 &integrity_write_entry.attr,
333 NULL,
334};
335
336static const struct sysfs_ops integrity_ops = {
337 .show = &integrity_attr_show,
338 .store = &integrity_attr_store,
339};
340
341static int __init blk_dev_integrity_init(void)
342{
343 integrity_cachep = kmem_cache_create("blkdev_integrity",
344 sizeof(struct blk_integrity),
345 0, SLAB_PANIC, NULL);
346 return 0;
347}
348subsys_initcall(blk_dev_integrity_init);
349
350static void blk_integrity_release(struct kobject *kobj)
351{
352 struct blk_integrity *bi =
353 container_of(kobj, struct blk_integrity, kobj);
354
355 kmem_cache_free(integrity_cachep, bi);
356}
357
358static struct kobj_type integrity_ktype = {
359 .default_attrs = integrity_attrs,
360 .sysfs_ops = &integrity_ops,
361 .release = blk_integrity_release,
362};
363
364bool blk_integrity_is_initialized(struct gendisk *disk)
365{
366 struct blk_integrity *bi = blk_get_integrity(disk);
367
368 return (bi && bi->name && strcmp(bi->name, bi_unsupported_name) != 0);
369}
370EXPORT_SYMBOL(blk_integrity_is_initialized);
371
372/**
373 * blk_integrity_register - Register a gendisk as being integrity-capable
374 * @disk: struct gendisk pointer to make integrity-aware
375 * @template: optional integrity profile to register
376 *
377 * Description: When a device needs to advertise itself as being able
378 * to send/receive integrity metadata it must use this function to
379 * register the capability with the block layer. The template is a
380 * blk_integrity struct with values appropriate for the underlying
381 * hardware. If template is NULL the new profile is allocated but
382 * not filled out. See Documentation/block/data-integrity.txt.
383 */
384int blk_integrity_register(struct gendisk *disk, struct blk_integrity *template)
385{
386 struct blk_integrity *bi;
387
388 BUG_ON(disk == NULL);
389
390 if (disk->integrity == NULL) {
391 bi = kmem_cache_alloc(integrity_cachep,
392 GFP_KERNEL | __GFP_ZERO);
393 if (!bi)
394 return -1;
395
396 if (kobject_init_and_add(&bi->kobj, &integrity_ktype,
397 &disk_to_dev(disk)->kobj,
398 "%s", "integrity")) {
399 kmem_cache_free(integrity_cachep, bi);
400 return -1;
401 }
402
403 kobject_uevent(&bi->kobj, KOBJ_ADD);
404
405 bi->flags |= INTEGRITY_FLAG_READ | INTEGRITY_FLAG_WRITE;
406 bi->sector_size = queue_logical_block_size(disk->queue);
407 disk->integrity = bi;
408 } else
409 bi = disk->integrity;
410
411 /* Use the provided profile as template */
412 if (template != NULL) {
413 bi->name = template->name;
414 bi->generate_fn = template->generate_fn;
415 bi->verify_fn = template->verify_fn;
416 bi->tuple_size = template->tuple_size;
417 bi->set_tag_fn = template->set_tag_fn;
418 bi->get_tag_fn = template->get_tag_fn;
419 bi->tag_size = template->tag_size;
420 } else
421 bi->name = bi_unsupported_name;
422
423 return 0;
424}
425EXPORT_SYMBOL(blk_integrity_register);
426
427/**
428 * blk_integrity_unregister - Remove block integrity profile
429 * @disk: disk whose integrity profile to deallocate
430 *
431 * Description: This function frees all memory used by the block
432 * integrity profile. To be called at device teardown.
433 */
434void blk_integrity_unregister(struct gendisk *disk)
435{
436 struct blk_integrity *bi;
437
438 if (!disk || !disk->integrity)
439 return;
440
441 bi = disk->integrity;
442
443 kobject_uevent(&bi->kobj, KOBJ_REMOVE);
444 kobject_del(&bi->kobj);
445 kobject_put(&bi->kobj);
446 disk->integrity = NULL;
447}
448EXPORT_SYMBOL(blk_integrity_unregister);
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}