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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 struct bvec_iter iter;
50 int prev = 0;
51
52 bio_for_each_integrity_vec(iv, bio, iter) {
53
54 if (prev) {
55 if (!BIOVEC_PHYS_MERGEABLE(&ivprv, &iv))
56 goto new_segment;
57
58 if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv))
59 goto new_segment;
60
61 if (seg_size + iv.bv_len > queue_max_segment_size(q))
62 goto new_segment;
63
64 seg_size += iv.bv_len;
65 } else {
66new_segment:
67 segments++;
68 seg_size = iv.bv_len;
69 }
70
71 prev = 1;
72 ivprv = iv;
73 }
74
75 return segments;
76}
77EXPORT_SYMBOL(blk_rq_count_integrity_sg);
78
79/**
80 * blk_rq_map_integrity_sg - Map integrity metadata into a scatterlist
81 * @q: request queue
82 * @bio: bio with integrity metadata attached
83 * @sglist: target scatterlist
84 *
85 * Description: Map the integrity vectors in request into a
86 * scatterlist. The scatterlist must be big enough to hold all
87 * elements. I.e. sized using blk_rq_count_integrity_sg().
88 */
89int blk_rq_map_integrity_sg(struct request_queue *q, struct bio *bio,
90 struct scatterlist *sglist)
91{
92 struct bio_vec iv, ivprv = { NULL };
93 struct scatterlist *sg = NULL;
94 unsigned int segments = 0;
95 struct bvec_iter iter;
96 int prev = 0;
97
98 bio_for_each_integrity_vec(iv, bio, iter) {
99
100 if (prev) {
101 if (!BIOVEC_PHYS_MERGEABLE(&ivprv, &iv))
102 goto new_segment;
103
104 if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv))
105 goto new_segment;
106
107 if (sg->length + iv.bv_len > queue_max_segment_size(q))
108 goto new_segment;
109
110 sg->length += iv.bv_len;
111 } else {
112new_segment:
113 if (!sg)
114 sg = sglist;
115 else {
116 sg_unmark_end(sg);
117 sg = sg_next(sg);
118 }
119
120 sg_set_page(sg, iv.bv_page, iv.bv_len, iv.bv_offset);
121 segments++;
122 }
123
124 prev = 1;
125 ivprv = iv;
126 }
127
128 if (sg)
129 sg_mark_end(sg);
130
131 return segments;
132}
133EXPORT_SYMBOL(blk_rq_map_integrity_sg);
134
135/**
136 * blk_integrity_compare - Compare integrity profile of two disks
137 * @gd1: Disk to compare
138 * @gd2: Disk to compare
139 *
140 * Description: Meta-devices like DM and MD need to verify that all
141 * sub-devices use the same integrity format before advertising to
142 * upper layers that they can send/receive integrity metadata. This
143 * function can be used to check whether two gendisk devices have
144 * compatible integrity formats.
145 */
146int blk_integrity_compare(struct gendisk *gd1, struct gendisk *gd2)
147{
148 struct blk_integrity *b1 = gd1->integrity;
149 struct blk_integrity *b2 = gd2->integrity;
150
151 if (!b1 && !b2)
152 return 0;
153
154 if (!b1 || !b2)
155 return -1;
156
157 if (b1->sector_size != b2->sector_size) {
158 printk(KERN_ERR "%s: %s/%s sector sz %u != %u\n", __func__,
159 gd1->disk_name, gd2->disk_name,
160 b1->sector_size, b2->sector_size);
161 return -1;
162 }
163
164 if (b1->tuple_size != b2->tuple_size) {
165 printk(KERN_ERR "%s: %s/%s tuple sz %u != %u\n", __func__,
166 gd1->disk_name, gd2->disk_name,
167 b1->tuple_size, b2->tuple_size);
168 return -1;
169 }
170
171 if (b1->tag_size && b2->tag_size && (b1->tag_size != b2->tag_size)) {
172 printk(KERN_ERR "%s: %s/%s tag sz %u != %u\n", __func__,
173 gd1->disk_name, gd2->disk_name,
174 b1->tag_size, b2->tag_size);
175 return -1;
176 }
177
178 if (strcmp(b1->name, b2->name)) {
179 printk(KERN_ERR "%s: %s/%s type %s != %s\n", __func__,
180 gd1->disk_name, gd2->disk_name,
181 b1->name, b2->name);
182 return -1;
183 }
184
185 return 0;
186}
187EXPORT_SYMBOL(blk_integrity_compare);
188
189int blk_integrity_merge_rq(struct request_queue *q, struct request *req,
190 struct request *next)
191{
192 if (blk_integrity_rq(req) != blk_integrity_rq(next))
193 return -1;
194
195 if (req->nr_integrity_segments + next->nr_integrity_segments >
196 q->limits.max_integrity_segments)
197 return -1;
198
199 return 0;
200}
201EXPORT_SYMBOL(blk_integrity_merge_rq);
202
203int blk_integrity_merge_bio(struct request_queue *q, struct request *req,
204 struct bio *bio)
205{
206 int nr_integrity_segs;
207 struct bio *next = bio->bi_next;
208
209 bio->bi_next = NULL;
210 nr_integrity_segs = blk_rq_count_integrity_sg(q, bio);
211 bio->bi_next = next;
212
213 if (req->nr_integrity_segments + nr_integrity_segs >
214 q->limits.max_integrity_segments)
215 return -1;
216
217 req->nr_integrity_segments += nr_integrity_segs;
218
219 return 0;
220}
221EXPORT_SYMBOL(blk_integrity_merge_bio);
222
223struct integrity_sysfs_entry {
224 struct attribute attr;
225 ssize_t (*show)(struct blk_integrity *, char *);
226 ssize_t (*store)(struct blk_integrity *, const char *, size_t);
227};
228
229static ssize_t integrity_attr_show(struct kobject *kobj, struct attribute *attr,
230 char *page)
231{
232 struct blk_integrity *bi =
233 container_of(kobj, struct blk_integrity, kobj);
234 struct integrity_sysfs_entry *entry =
235 container_of(attr, struct integrity_sysfs_entry, attr);
236
237 return entry->show(bi, page);
238}
239
240static ssize_t integrity_attr_store(struct kobject *kobj,
241 struct attribute *attr, const char *page,
242 size_t count)
243{
244 struct blk_integrity *bi =
245 container_of(kobj, struct blk_integrity, kobj);
246 struct integrity_sysfs_entry *entry =
247 container_of(attr, struct integrity_sysfs_entry, attr);
248 ssize_t ret = 0;
249
250 if (entry->store)
251 ret = entry->store(bi, page, count);
252
253 return ret;
254}
255
256static ssize_t integrity_format_show(struct blk_integrity *bi, char *page)
257{
258 if (bi != NULL && bi->name != NULL)
259 return sprintf(page, "%s\n", bi->name);
260 else
261 return sprintf(page, "none\n");
262}
263
264static ssize_t integrity_tag_size_show(struct blk_integrity *bi, char *page)
265{
266 if (bi != NULL)
267 return sprintf(page, "%u\n", bi->tag_size);
268 else
269 return sprintf(page, "0\n");
270}
271
272static ssize_t integrity_read_store(struct blk_integrity *bi,
273 const char *page, size_t count)
274{
275 char *p = (char *) page;
276 unsigned long val = simple_strtoul(p, &p, 10);
277
278 if (val)
279 bi->flags |= INTEGRITY_FLAG_READ;
280 else
281 bi->flags &= ~INTEGRITY_FLAG_READ;
282
283 return count;
284}
285
286static ssize_t integrity_read_show(struct blk_integrity *bi, char *page)
287{
288 return sprintf(page, "%d\n", (bi->flags & INTEGRITY_FLAG_READ) != 0);
289}
290
291static ssize_t integrity_write_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 |= INTEGRITY_FLAG_WRITE;
299 else
300 bi->flags &= ~INTEGRITY_FLAG_WRITE;
301
302 return count;
303}
304
305static ssize_t integrity_write_show(struct blk_integrity *bi, char *page)
306{
307 return sprintf(page, "%d\n", (bi->flags & INTEGRITY_FLAG_WRITE) != 0);
308}
309
310static struct integrity_sysfs_entry integrity_format_entry = {
311 .attr = { .name = "format", .mode = S_IRUGO },
312 .show = integrity_format_show,
313};
314
315static struct integrity_sysfs_entry integrity_tag_size_entry = {
316 .attr = { .name = "tag_size", .mode = S_IRUGO },
317 .show = integrity_tag_size_show,
318};
319
320static struct integrity_sysfs_entry integrity_read_entry = {
321 .attr = { .name = "read_verify", .mode = S_IRUGO | S_IWUSR },
322 .show = integrity_read_show,
323 .store = integrity_read_store,
324};
325
326static struct integrity_sysfs_entry integrity_write_entry = {
327 .attr = { .name = "write_generate", .mode = S_IRUGO | S_IWUSR },
328 .show = integrity_write_show,
329 .store = integrity_write_store,
330};
331
332static struct attribute *integrity_attrs[] = {
333 &integrity_format_entry.attr,
334 &integrity_tag_size_entry.attr,
335 &integrity_read_entry.attr,
336 &integrity_write_entry.attr,
337 NULL,
338};
339
340static const struct sysfs_ops integrity_ops = {
341 .show = &integrity_attr_show,
342 .store = &integrity_attr_store,
343};
344
345static int __init blk_dev_integrity_init(void)
346{
347 integrity_cachep = kmem_cache_create("blkdev_integrity",
348 sizeof(struct blk_integrity),
349 0, SLAB_PANIC, NULL);
350 return 0;
351}
352subsys_initcall(blk_dev_integrity_init);
353
354static void blk_integrity_release(struct kobject *kobj)
355{
356 struct blk_integrity *bi =
357 container_of(kobj, struct blk_integrity, kobj);
358
359 kmem_cache_free(integrity_cachep, bi);
360}
361
362static struct kobj_type integrity_ktype = {
363 .default_attrs = integrity_attrs,
364 .sysfs_ops = &integrity_ops,
365 .release = blk_integrity_release,
366};
367
368bool blk_integrity_is_initialized(struct gendisk *disk)
369{
370 struct blk_integrity *bi = blk_get_integrity(disk);
371
372 return (bi && bi->name && strcmp(bi->name, bi_unsupported_name) != 0);
373}
374EXPORT_SYMBOL(blk_integrity_is_initialized);
375
376/**
377 * blk_integrity_register - Register a gendisk as being integrity-capable
378 * @disk: struct gendisk pointer to make integrity-aware
379 * @template: optional integrity profile to register
380 *
381 * Description: When a device needs to advertise itself as being able
382 * to send/receive integrity metadata it must use this function to
383 * register the capability with the block layer. The template is a
384 * blk_integrity struct with values appropriate for the underlying
385 * hardware. If template is NULL the new profile is allocated but
386 * not filled out. See Documentation/block/data-integrity.txt.
387 */
388int blk_integrity_register(struct gendisk *disk, struct blk_integrity *template)
389{
390 struct blk_integrity *bi;
391
392 BUG_ON(disk == NULL);
393
394 if (disk->integrity == NULL) {
395 bi = kmem_cache_alloc(integrity_cachep,
396 GFP_KERNEL | __GFP_ZERO);
397 if (!bi)
398 return -1;
399
400 if (kobject_init_and_add(&bi->kobj, &integrity_ktype,
401 &disk_to_dev(disk)->kobj,
402 "%s", "integrity")) {
403 kmem_cache_free(integrity_cachep, bi);
404 return -1;
405 }
406
407 kobject_uevent(&bi->kobj, KOBJ_ADD);
408
409 bi->flags |= INTEGRITY_FLAG_READ | INTEGRITY_FLAG_WRITE;
410 bi->sector_size = queue_logical_block_size(disk->queue);
411 disk->integrity = bi;
412 } else
413 bi = disk->integrity;
414
415 /* Use the provided profile as template */
416 if (template != NULL) {
417 bi->name = template->name;
418 bi->generate_fn = template->generate_fn;
419 bi->verify_fn = template->verify_fn;
420 bi->tuple_size = template->tuple_size;
421 bi->set_tag_fn = template->set_tag_fn;
422 bi->get_tag_fn = template->get_tag_fn;
423 bi->tag_size = template->tag_size;
424 } else
425 bi->name = bi_unsupported_name;
426
427 disk->queue->backing_dev_info.capabilities |= BDI_CAP_STABLE_WRITES;
428
429 return 0;
430}
431EXPORT_SYMBOL(blk_integrity_register);
432
433/**
434 * blk_integrity_unregister - Remove block integrity profile
435 * @disk: disk whose integrity profile to deallocate
436 *
437 * Description: This function frees all memory used by the block
438 * integrity profile. To be called at device teardown.
439 */
440void blk_integrity_unregister(struct gendisk *disk)
441{
442 struct blk_integrity *bi;
443
444 if (!disk || !disk->integrity)
445 return;
446
447 disk->queue->backing_dev_info.capabilities &= ~BDI_CAP_STABLE_WRITES;
448
449 bi = disk->integrity;
450
451 kobject_uevent(&bi->kobj, KOBJ_REMOVE);
452 kobject_del(&bi->kobj);
453 kobject_put(&bi->kobj);
454 disk->integrity = NULL;
455}
456EXPORT_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/blk-integrity.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}
186
187bool blk_integrity_merge_bio(struct request_queue *q, struct request *req,
188 struct bio *bio)
189{
190 int nr_integrity_segs;
191 struct bio *next = bio->bi_next;
192
193 if (blk_integrity_rq(req) == 0 && bio_integrity(bio) == NULL)
194 return true;
195
196 if (blk_integrity_rq(req) == 0 || bio_integrity(bio) == NULL)
197 return false;
198
199 if (bio_integrity(req->bio)->bip_flags != bio_integrity(bio)->bip_flags)
200 return false;
201
202 bio->bi_next = NULL;
203 nr_integrity_segs = blk_rq_count_integrity_sg(q, bio);
204 bio->bi_next = next;
205
206 if (req->nr_integrity_segments + nr_integrity_segs >
207 q->limits.max_integrity_segments)
208 return false;
209
210 req->nr_integrity_segments += nr_integrity_segs;
211
212 return true;
213}
214
215static inline struct blk_integrity *dev_to_bi(struct device *dev)
216{
217 return &dev_to_disk(dev)->queue->integrity;
218}
219
220static ssize_t format_show(struct device *dev, struct device_attribute *attr,
221 char *page)
222{
223 struct blk_integrity *bi = dev_to_bi(dev);
224
225 if (bi->profile && bi->profile->name)
226 return sysfs_emit(page, "%s\n", bi->profile->name);
227 return sysfs_emit(page, "none\n");
228}
229
230static ssize_t tag_size_show(struct device *dev, struct device_attribute *attr,
231 char *page)
232{
233 struct blk_integrity *bi = dev_to_bi(dev);
234
235 return sysfs_emit(page, "%u\n", bi->tag_size);
236}
237
238static ssize_t protection_interval_bytes_show(struct device *dev,
239 struct device_attribute *attr,
240 char *page)
241{
242 struct blk_integrity *bi = dev_to_bi(dev);
243
244 return sysfs_emit(page, "%u\n",
245 bi->interval_exp ? 1 << bi->interval_exp : 0);
246}
247
248static ssize_t read_verify_store(struct device *dev,
249 struct device_attribute *attr,
250 const char *page, size_t count)
251{
252 struct blk_integrity *bi = dev_to_bi(dev);
253 char *p = (char *) page;
254 unsigned long val = simple_strtoul(p, &p, 10);
255
256 if (val)
257 bi->flags |= BLK_INTEGRITY_VERIFY;
258 else
259 bi->flags &= ~BLK_INTEGRITY_VERIFY;
260
261 return count;
262}
263
264static ssize_t read_verify_show(struct device *dev,
265 struct device_attribute *attr, char *page)
266{
267 struct blk_integrity *bi = dev_to_bi(dev);
268
269 return sysfs_emit(page, "%d\n", !!(bi->flags & BLK_INTEGRITY_VERIFY));
270}
271
272static ssize_t write_generate_store(struct device *dev,
273 struct device_attribute *attr,
274 const char *page, size_t count)
275{
276 struct blk_integrity *bi = dev_to_bi(dev);
277
278 char *p = (char *) page;
279 unsigned long val = simple_strtoul(p, &p, 10);
280
281 if (val)
282 bi->flags |= BLK_INTEGRITY_GENERATE;
283 else
284 bi->flags &= ~BLK_INTEGRITY_GENERATE;
285
286 return count;
287}
288
289static ssize_t write_generate_show(struct device *dev,
290 struct device_attribute *attr, char *page)
291{
292 struct blk_integrity *bi = dev_to_bi(dev);
293
294 return sysfs_emit(page, "%d\n", !!(bi->flags & BLK_INTEGRITY_GENERATE));
295}
296
297static ssize_t device_is_integrity_capable_show(struct device *dev,
298 struct device_attribute *attr,
299 char *page)
300{
301 struct blk_integrity *bi = dev_to_bi(dev);
302
303 return sysfs_emit(page, "%u\n",
304 !!(bi->flags & BLK_INTEGRITY_DEVICE_CAPABLE));
305}
306
307static DEVICE_ATTR_RO(format);
308static DEVICE_ATTR_RO(tag_size);
309static DEVICE_ATTR_RO(protection_interval_bytes);
310static DEVICE_ATTR_RW(read_verify);
311static DEVICE_ATTR_RW(write_generate);
312static DEVICE_ATTR_RO(device_is_integrity_capable);
313
314static struct attribute *integrity_attrs[] = {
315 &dev_attr_format.attr,
316 &dev_attr_tag_size.attr,
317 &dev_attr_protection_interval_bytes.attr,
318 &dev_attr_read_verify.attr,
319 &dev_attr_write_generate.attr,
320 &dev_attr_device_is_integrity_capable.attr,
321 NULL
322};
323
324const struct attribute_group blk_integrity_attr_group = {
325 .name = "integrity",
326 .attrs = integrity_attrs,
327};
328
329static blk_status_t blk_integrity_nop_fn(struct blk_integrity_iter *iter)
330{
331 return BLK_STS_OK;
332}
333
334static void blk_integrity_nop_prepare(struct request *rq)
335{
336}
337
338static void blk_integrity_nop_complete(struct request *rq,
339 unsigned int nr_bytes)
340{
341}
342
343static const struct blk_integrity_profile nop_profile = {
344 .name = "nop",
345 .generate_fn = blk_integrity_nop_fn,
346 .verify_fn = blk_integrity_nop_fn,
347 .prepare_fn = blk_integrity_nop_prepare,
348 .complete_fn = blk_integrity_nop_complete,
349};
350
351/**
352 * blk_integrity_register - Register a gendisk as being integrity-capable
353 * @disk: struct gendisk pointer to make integrity-aware
354 * @template: block integrity profile to register
355 *
356 * Description: When a device needs to advertise itself as being able to
357 * send/receive integrity metadata it must use this function to register
358 * the capability with the block layer. The template is a blk_integrity
359 * struct with values appropriate for the underlying hardware. See
360 * Documentation/block/data-integrity.rst.
361 */
362void blk_integrity_register(struct gendisk *disk, struct blk_integrity *template)
363{
364 struct blk_integrity *bi = &disk->queue->integrity;
365
366 bi->flags = BLK_INTEGRITY_VERIFY | BLK_INTEGRITY_GENERATE |
367 template->flags;
368 bi->interval_exp = template->interval_exp ? :
369 ilog2(queue_logical_block_size(disk->queue));
370 bi->profile = template->profile ? template->profile : &nop_profile;
371 bi->tuple_size = template->tuple_size;
372 bi->tag_size = template->tag_size;
373
374 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, disk->queue);
375
376#ifdef CONFIG_BLK_INLINE_ENCRYPTION
377 if (disk->queue->crypto_profile) {
378 pr_warn("blk-integrity: Integrity and hardware inline encryption are not supported together. Disabling hardware inline encryption.\n");
379 disk->queue->crypto_profile = NULL;
380 }
381#endif
382}
383EXPORT_SYMBOL(blk_integrity_register);
384
385/**
386 * blk_integrity_unregister - Unregister block integrity profile
387 * @disk: disk whose integrity profile to unregister
388 *
389 * Description: This function unregisters the integrity capability from
390 * a block device.
391 */
392void blk_integrity_unregister(struct gendisk *disk)
393{
394 struct blk_integrity *bi = &disk->queue->integrity;
395
396 if (!bi->profile)
397 return;
398
399 /* ensure all bios are off the integrity workqueue */
400 blk_flush_integrity();
401 blk_queue_flag_clear(QUEUE_FLAG_STABLE_WRITES, disk->queue);
402 memset(bi, 0, sizeof(*bi));
403}
404EXPORT_SYMBOL(blk_integrity_unregister);