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7ba1ba12 MP |
1 | /* |
2 | * bio-integrity.c - bio 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/workqueue.h> | |
27 | ||
28 | static struct kmem_cache *bio_integrity_slab __read_mostly; | |
29 | static struct workqueue_struct *kintegrityd_wq; | |
30 | ||
31 | /** | |
32 | * bio_integrity_alloc_bioset - Allocate integrity payload and attach it to bio | |
33 | * @bio: bio to attach integrity metadata to | |
34 | * @gfp_mask: Memory allocation mask | |
35 | * @nr_vecs: Number of integrity metadata scatter-gather elements | |
36 | * @bs: bio_set to allocate from | |
37 | * | |
38 | * Description: This function prepares a bio for attaching integrity | |
39 | * metadata. nr_vecs specifies the maximum number of pages containing | |
40 | * integrity metadata that can be attached. | |
41 | */ | |
b984679e JA |
42 | struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *bio, |
43 | gfp_t gfp_mask, | |
44 | unsigned int nr_vecs, | |
45 | struct bio_set *bs) | |
7ba1ba12 MP |
46 | { |
47 | struct bio_integrity_payload *bip; | |
48 | struct bio_vec *iv; | |
49 | unsigned long idx; | |
50 | ||
51 | BUG_ON(bio == NULL); | |
52 | ||
53 | bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask); | |
54 | if (unlikely(bip == NULL)) { | |
55 | printk(KERN_ERR "%s: could not alloc bip\n", __func__); | |
56 | return NULL; | |
57 | } | |
58 | ||
59 | memset(bip, 0, sizeof(*bip)); | |
60 | ||
61 | iv = bvec_alloc_bs(gfp_mask, nr_vecs, &idx, bs); | |
62 | if (unlikely(iv == NULL)) { | |
63 | printk(KERN_ERR "%s: could not alloc bip_vec\n", __func__); | |
64 | mempool_free(bip, bs->bio_integrity_pool); | |
65 | return NULL; | |
66 | } | |
67 | ||
68 | bip->bip_pool = idx; | |
69 | bip->bip_vec = iv; | |
70 | bip->bip_bio = bio; | |
71 | bio->bi_integrity = bip; | |
72 | ||
73 | return bip; | |
74 | } | |
75 | EXPORT_SYMBOL(bio_integrity_alloc_bioset); | |
76 | ||
77 | /** | |
78 | * bio_integrity_alloc - Allocate integrity payload and attach it to bio | |
79 | * @bio: bio to attach integrity metadata to | |
80 | * @gfp_mask: Memory allocation mask | |
81 | * @nr_vecs: Number of integrity metadata scatter-gather elements | |
82 | * | |
83 | * Description: This function prepares a bio for attaching integrity | |
84 | * metadata. nr_vecs specifies the maximum number of pages containing | |
85 | * integrity metadata that can be attached. | |
86 | */ | |
b984679e JA |
87 | struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, |
88 | gfp_t gfp_mask, | |
89 | unsigned int nr_vecs) | |
7ba1ba12 MP |
90 | { |
91 | return bio_integrity_alloc_bioset(bio, gfp_mask, nr_vecs, fs_bio_set); | |
92 | } | |
93 | EXPORT_SYMBOL(bio_integrity_alloc); | |
94 | ||
95 | /** | |
96 | * bio_integrity_free - Free bio integrity payload | |
97 | * @bio: bio containing bip to be freed | |
98 | * @bs: bio_set this bio was allocated from | |
99 | * | |
100 | * Description: Used to free the integrity portion of a bio. Usually | |
101 | * called from bio_free(). | |
102 | */ | |
103 | void bio_integrity_free(struct bio *bio, struct bio_set *bs) | |
104 | { | |
105 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
106 | ||
107 | BUG_ON(bip == NULL); | |
108 | ||
109 | /* A cloned bio doesn't own the integrity metadata */ | |
110 | if (!bio_flagged(bio, BIO_CLONED) && bip->bip_buf != NULL) | |
111 | kfree(bip->bip_buf); | |
112 | ||
113 | mempool_free(bip->bip_vec, bs->bvec_pools[bip->bip_pool]); | |
114 | mempool_free(bip, bs->bio_integrity_pool); | |
115 | ||
116 | bio->bi_integrity = NULL; | |
117 | } | |
118 | EXPORT_SYMBOL(bio_integrity_free); | |
119 | ||
120 | /** | |
121 | * bio_integrity_add_page - Attach integrity metadata | |
122 | * @bio: bio to update | |
123 | * @page: page containing integrity metadata | |
124 | * @len: number of bytes of integrity metadata in page | |
125 | * @offset: start offset within page | |
126 | * | |
127 | * Description: Attach a page containing integrity metadata to bio. | |
128 | */ | |
129 | int bio_integrity_add_page(struct bio *bio, struct page *page, | |
130 | unsigned int len, unsigned int offset) | |
131 | { | |
132 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
133 | struct bio_vec *iv; | |
134 | ||
135 | if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_pool)) { | |
136 | printk(KERN_ERR "%s: bip_vec full\n", __func__); | |
137 | return 0; | |
138 | } | |
139 | ||
140 | iv = bip_vec_idx(bip, bip->bip_vcnt); | |
141 | BUG_ON(iv == NULL); | |
142 | BUG_ON(iv->bv_page != NULL); | |
143 | ||
144 | iv->bv_page = page; | |
145 | iv->bv_len = len; | |
146 | iv->bv_offset = offset; | |
147 | bip->bip_vcnt++; | |
148 | ||
149 | return len; | |
150 | } | |
151 | EXPORT_SYMBOL(bio_integrity_add_page); | |
152 | ||
153 | /** | |
154 | * bio_integrity_enabled - Check whether integrity can be passed | |
155 | * @bio: bio to check | |
156 | * | |
157 | * Description: Determines whether bio_integrity_prep() can be called | |
158 | * on this bio or not. bio data direction and target device must be | |
159 | * set prior to calling. The functions honors the write_generate and | |
160 | * read_verify flags in sysfs. | |
161 | */ | |
162 | int bio_integrity_enabled(struct bio *bio) | |
163 | { | |
164 | /* Already protected? */ | |
165 | if (bio_integrity(bio)) | |
166 | return 0; | |
167 | ||
168 | return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio)); | |
169 | } | |
170 | EXPORT_SYMBOL(bio_integrity_enabled); | |
171 | ||
172 | /** | |
173 | * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto | |
174 | * @bi: blk_integrity profile for device | |
175 | * @sectors: Number of 512 sectors to convert | |
176 | * | |
177 | * Description: The block layer calculates everything in 512 byte | |
178 | * sectors but integrity metadata is done in terms of the hardware | |
179 | * sector size of the storage device. Convert the block layer sectors | |
180 | * to physical sectors. | |
181 | */ | |
b984679e JA |
182 | static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi, |
183 | unsigned int sectors) | |
7ba1ba12 MP |
184 | { |
185 | /* At this point there are only 512b or 4096b DIF/EPP devices */ | |
186 | if (bi->sector_size == 4096) | |
187 | return sectors >>= 3; | |
188 | ||
189 | return sectors; | |
190 | } | |
191 | ||
192 | /** | |
193 | * bio_integrity_tag_size - Retrieve integrity tag space | |
194 | * @bio: bio to inspect | |
195 | * | |
196 | * Description: Returns the maximum number of tag bytes that can be | |
197 | * attached to this bio. Filesystems can use this to determine how | |
198 | * much metadata to attach to an I/O. | |
199 | */ | |
200 | unsigned int bio_integrity_tag_size(struct bio *bio) | |
201 | { | |
202 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
203 | ||
204 | BUG_ON(bio->bi_size == 0); | |
205 | ||
206 | return bi->tag_size * (bio->bi_size / bi->sector_size); | |
207 | } | |
208 | EXPORT_SYMBOL(bio_integrity_tag_size); | |
209 | ||
210 | int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, int set) | |
211 | { | |
212 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
213 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
214 | unsigned int nr_sectors; | |
215 | ||
216 | BUG_ON(bip->bip_buf == NULL); | |
217 | ||
218 | if (bi->tag_size == 0) | |
219 | return -1; | |
220 | ||
b984679e JA |
221 | nr_sectors = bio_integrity_hw_sectors(bi, |
222 | DIV_ROUND_UP(len, bi->tag_size)); | |
7ba1ba12 MP |
223 | |
224 | if (nr_sectors * bi->tuple_size > bip->bip_size) { | |
225 | printk(KERN_ERR "%s: tag too big for bio: %u > %u\n", | |
226 | __func__, nr_sectors * bi->tuple_size, bip->bip_size); | |
227 | return -1; | |
228 | } | |
229 | ||
230 | if (set) | |
231 | bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors); | |
232 | else | |
233 | bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors); | |
234 | ||
235 | return 0; | |
236 | } | |
237 | ||
238 | /** | |
239 | * bio_integrity_set_tag - Attach a tag buffer to a bio | |
240 | * @bio: bio to attach buffer to | |
241 | * @tag_buf: Pointer to a buffer containing tag data | |
242 | * @len: Length of the included buffer | |
243 | * | |
244 | * Description: Use this function to tag a bio by leveraging the extra | |
245 | * space provided by devices formatted with integrity protection. The | |
246 | * size of the integrity buffer must be <= to the size reported by | |
247 | * bio_integrity_tag_size(). | |
248 | */ | |
249 | int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len) | |
250 | { | |
251 | BUG_ON(bio_data_dir(bio) != WRITE); | |
252 | ||
253 | return bio_integrity_tag(bio, tag_buf, len, 1); | |
254 | } | |
255 | EXPORT_SYMBOL(bio_integrity_set_tag); | |
256 | ||
257 | /** | |
258 | * bio_integrity_get_tag - Retrieve a tag buffer from a bio | |
259 | * @bio: bio to retrieve buffer from | |
260 | * @tag_buf: Pointer to a buffer for the tag data | |
261 | * @len: Length of the target buffer | |
262 | * | |
263 | * Description: Use this function to retrieve the tag buffer from a | |
264 | * completed I/O. The size of the integrity buffer must be <= to the | |
265 | * size reported by bio_integrity_tag_size(). | |
266 | */ | |
267 | int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len) | |
268 | { | |
269 | BUG_ON(bio_data_dir(bio) != READ); | |
270 | ||
271 | return bio_integrity_tag(bio, tag_buf, len, 0); | |
272 | } | |
273 | EXPORT_SYMBOL(bio_integrity_get_tag); | |
274 | ||
275 | /** | |
276 | * bio_integrity_generate - Generate integrity metadata for a bio | |
277 | * @bio: bio to generate integrity metadata for | |
278 | * | |
279 | * Description: Generates integrity metadata for a bio by calling the | |
280 | * block device's generation callback function. The bio must have a | |
281 | * bip attached with enough room to accommodate the generated | |
282 | * integrity metadata. | |
283 | */ | |
284 | static void bio_integrity_generate(struct bio *bio) | |
285 | { | |
286 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
287 | struct blk_integrity_exchg bix; | |
288 | struct bio_vec *bv; | |
289 | sector_t sector = bio->bi_sector; | |
290 | unsigned int i, sectors, total; | |
291 | void *prot_buf = bio->bi_integrity->bip_buf; | |
292 | ||
293 | total = 0; | |
294 | bix.disk_name = bio->bi_bdev->bd_disk->disk_name; | |
295 | bix.sector_size = bi->sector_size; | |
296 | ||
297 | bio_for_each_segment(bv, bio, i) { | |
298 | void *kaddr = kmap_atomic(bv->bv_page, KM_USER0); | |
299 | bix.data_buf = kaddr + bv->bv_offset; | |
300 | bix.data_size = bv->bv_len; | |
301 | bix.prot_buf = prot_buf; | |
302 | bix.sector = sector; | |
303 | ||
304 | bi->generate_fn(&bix); | |
305 | ||
306 | sectors = bv->bv_len / bi->sector_size; | |
307 | sector += sectors; | |
308 | prot_buf += sectors * bi->tuple_size; | |
309 | total += sectors * bi->tuple_size; | |
310 | BUG_ON(total > bio->bi_integrity->bip_size); | |
311 | ||
312 | kunmap_atomic(kaddr, KM_USER0); | |
313 | } | |
314 | } | |
315 | ||
316 | /** | |
317 | * bio_integrity_prep - Prepare bio for integrity I/O | |
318 | * @bio: bio to prepare | |
319 | * | |
320 | * Description: Allocates a buffer for integrity metadata, maps the | |
321 | * pages and attaches them to a bio. The bio must have data | |
322 | * direction, target device and start sector set priot to calling. In | |
323 | * the WRITE case, integrity metadata will be generated using the | |
324 | * block device's integrity function. In the READ case, the buffer | |
325 | * will be prepared for DMA and a suitable end_io handler set up. | |
326 | */ | |
327 | int bio_integrity_prep(struct bio *bio) | |
328 | { | |
329 | struct bio_integrity_payload *bip; | |
330 | struct blk_integrity *bi; | |
331 | struct request_queue *q; | |
332 | void *buf; | |
333 | unsigned long start, end; | |
334 | unsigned int len, nr_pages; | |
335 | unsigned int bytes, offset, i; | |
336 | unsigned int sectors; | |
337 | ||
338 | bi = bdev_get_integrity(bio->bi_bdev); | |
339 | q = bdev_get_queue(bio->bi_bdev); | |
340 | BUG_ON(bi == NULL); | |
341 | BUG_ON(bio_integrity(bio)); | |
342 | ||
343 | sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio)); | |
344 | ||
345 | /* Allocate kernel buffer for protection data */ | |
346 | len = sectors * blk_integrity_tuple_size(bi); | |
347 | buf = kmalloc(len, GFP_NOIO | __GFP_NOFAIL | q->bounce_gfp); | |
348 | if (unlikely(buf == NULL)) { | |
349 | printk(KERN_ERR "could not allocate integrity buffer\n"); | |
350 | return -EIO; | |
351 | } | |
352 | ||
353 | end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
354 | start = ((unsigned long) buf) >> PAGE_SHIFT; | |
355 | nr_pages = end - start; | |
356 | ||
357 | /* Allocate bio integrity payload and integrity vectors */ | |
358 | bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages); | |
359 | if (unlikely(bip == NULL)) { | |
360 | printk(KERN_ERR "could not allocate data integrity bioset\n"); | |
361 | kfree(buf); | |
362 | return -EIO; | |
363 | } | |
364 | ||
365 | bip->bip_buf = buf; | |
366 | bip->bip_size = len; | |
367 | bip->bip_sector = bio->bi_sector; | |
368 | ||
369 | /* Map it */ | |
370 | offset = offset_in_page(buf); | |
371 | for (i = 0 ; i < nr_pages ; i++) { | |
372 | int ret; | |
373 | bytes = PAGE_SIZE - offset; | |
374 | ||
375 | if (len <= 0) | |
376 | break; | |
377 | ||
378 | if (bytes > len) | |
379 | bytes = len; | |
380 | ||
381 | ret = bio_integrity_add_page(bio, virt_to_page(buf), | |
382 | bytes, offset); | |
383 | ||
384 | if (ret == 0) | |
385 | return 0; | |
386 | ||
387 | if (ret < bytes) | |
388 | break; | |
389 | ||
390 | buf += bytes; | |
391 | len -= bytes; | |
392 | offset = 0; | |
393 | } | |
394 | ||
395 | /* Install custom I/O completion handler if read verify is enabled */ | |
396 | if (bio_data_dir(bio) == READ) { | |
397 | bip->bip_end_io = bio->bi_end_io; | |
398 | bio->bi_end_io = bio_integrity_endio; | |
399 | } | |
400 | ||
401 | /* Auto-generate integrity metadata if this is a write */ | |
402 | if (bio_data_dir(bio) == WRITE) | |
403 | bio_integrity_generate(bio); | |
404 | ||
405 | return 0; | |
406 | } | |
407 | EXPORT_SYMBOL(bio_integrity_prep); | |
408 | ||
409 | /** | |
410 | * bio_integrity_verify - Verify integrity metadata for a bio | |
411 | * @bio: bio to verify | |
412 | * | |
413 | * Description: This function is called to verify the integrity of a | |
414 | * bio. The data in the bio io_vec is compared to the integrity | |
415 | * metadata returned by the HBA. | |
416 | */ | |
417 | static int bio_integrity_verify(struct bio *bio) | |
418 | { | |
419 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
420 | struct blk_integrity_exchg bix; | |
421 | struct bio_vec *bv; | |
422 | sector_t sector = bio->bi_integrity->bip_sector; | |
423 | unsigned int i, sectors, total, ret; | |
424 | void *prot_buf = bio->bi_integrity->bip_buf; | |
425 | ||
426 | ret = total = 0; | |
427 | bix.disk_name = bio->bi_bdev->bd_disk->disk_name; | |
428 | bix.sector_size = bi->sector_size; | |
429 | ||
430 | bio_for_each_segment(bv, bio, i) { | |
431 | void *kaddr = kmap_atomic(bv->bv_page, KM_USER0); | |
432 | bix.data_buf = kaddr + bv->bv_offset; | |
433 | bix.data_size = bv->bv_len; | |
434 | bix.prot_buf = prot_buf; | |
435 | bix.sector = sector; | |
436 | ||
437 | ret = bi->verify_fn(&bix); | |
438 | ||
439 | if (ret) { | |
440 | kunmap_atomic(kaddr, KM_USER0); | |
441 | break; | |
442 | } | |
443 | ||
444 | sectors = bv->bv_len / bi->sector_size; | |
445 | sector += sectors; | |
446 | prot_buf += sectors * bi->tuple_size; | |
447 | total += sectors * bi->tuple_size; | |
448 | BUG_ON(total > bio->bi_integrity->bip_size); | |
449 | ||
450 | kunmap_atomic(kaddr, KM_USER0); | |
451 | } | |
452 | ||
453 | return ret; | |
454 | } | |
455 | ||
456 | /** | |
457 | * bio_integrity_verify_fn - Integrity I/O completion worker | |
458 | * @work: Work struct stored in bio to be verified | |
459 | * | |
460 | * Description: This workqueue function is called to complete a READ | |
461 | * request. The function verifies the transferred integrity metadata | |
462 | * and then calls the original bio end_io function. | |
463 | */ | |
464 | static void bio_integrity_verify_fn(struct work_struct *work) | |
465 | { | |
b984679e | 466 | struct bio_integrity_payload *bip = |
7ba1ba12 MP |
467 | container_of(work, struct bio_integrity_payload, bip_work); |
468 | struct bio *bio = bip->bip_bio; | |
469 | int error = bip->bip_error; | |
470 | ||
471 | if (bio_integrity_verify(bio)) { | |
472 | clear_bit(BIO_UPTODATE, &bio->bi_flags); | |
473 | error = -EIO; | |
474 | } | |
475 | ||
476 | /* Restore original bio completion handler */ | |
477 | bio->bi_end_io = bip->bip_end_io; | |
478 | ||
479 | if (bio->bi_end_io) | |
480 | bio->bi_end_io(bio, error); | |
481 | } | |
482 | ||
483 | /** | |
484 | * bio_integrity_endio - Integrity I/O completion function | |
485 | * @bio: Protected bio | |
486 | * @error: Pointer to errno | |
487 | * | |
488 | * Description: Completion for integrity I/O | |
489 | * | |
490 | * Normally I/O completion is done in interrupt context. However, | |
491 | * verifying I/O integrity is a time-consuming task which must be run | |
492 | * in process context. This function postpones completion | |
493 | * accordingly. | |
494 | */ | |
495 | void bio_integrity_endio(struct bio *bio, int error) | |
496 | { | |
497 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
498 | ||
499 | BUG_ON(bip->bip_bio != bio); | |
500 | ||
501 | bip->bip_error = error; | |
502 | INIT_WORK(&bip->bip_work, bio_integrity_verify_fn); | |
503 | queue_work(kintegrityd_wq, &bip->bip_work); | |
504 | } | |
505 | EXPORT_SYMBOL(bio_integrity_endio); | |
506 | ||
507 | /** | |
508 | * bio_integrity_mark_head - Advance bip_vec skip bytes | |
509 | * @bip: Integrity vector to advance | |
510 | * @skip: Number of bytes to advance it | |
511 | */ | |
b984679e JA |
512 | void bio_integrity_mark_head(struct bio_integrity_payload *bip, |
513 | unsigned int skip) | |
7ba1ba12 MP |
514 | { |
515 | struct bio_vec *iv; | |
516 | unsigned int i; | |
517 | ||
518 | bip_for_each_vec(iv, bip, i) { | |
519 | if (skip == 0) { | |
520 | bip->bip_idx = i; | |
521 | return; | |
522 | } else if (skip >= iv->bv_len) { | |
523 | skip -= iv->bv_len; | |
524 | } else { /* skip < iv->bv_len) */ | |
525 | iv->bv_offset += skip; | |
526 | iv->bv_len -= skip; | |
527 | bip->bip_idx = i; | |
528 | return; | |
529 | } | |
530 | } | |
531 | } | |
532 | ||
533 | /** | |
534 | * bio_integrity_mark_tail - Truncate bip_vec to be len bytes long | |
535 | * @bip: Integrity vector to truncate | |
536 | * @len: New length of integrity vector | |
537 | */ | |
b984679e JA |
538 | void bio_integrity_mark_tail(struct bio_integrity_payload *bip, |
539 | unsigned int len) | |
7ba1ba12 MP |
540 | { |
541 | struct bio_vec *iv; | |
542 | unsigned int i; | |
543 | ||
544 | bip_for_each_vec(iv, bip, i) { | |
545 | if (len == 0) { | |
546 | bip->bip_vcnt = i; | |
547 | return; | |
548 | } else if (len >= iv->bv_len) { | |
549 | len -= iv->bv_len; | |
550 | } else { /* len < iv->bv_len) */ | |
551 | iv->bv_len = len; | |
552 | len = 0; | |
553 | } | |
554 | } | |
555 | } | |
556 | ||
557 | /** | |
558 | * bio_integrity_advance - Advance integrity vector | |
559 | * @bio: bio whose integrity vector to update | |
560 | * @bytes_done: number of data bytes that have been completed | |
561 | * | |
562 | * Description: This function calculates how many integrity bytes the | |
563 | * number of completed data bytes correspond to and advances the | |
564 | * integrity vector accordingly. | |
565 | */ | |
566 | void bio_integrity_advance(struct bio *bio, unsigned int bytes_done) | |
567 | { | |
568 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
569 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
570 | unsigned int nr_sectors; | |
571 | ||
572 | BUG_ON(bip == NULL); | |
573 | BUG_ON(bi == NULL); | |
574 | ||
575 | nr_sectors = bio_integrity_hw_sectors(bi, bytes_done >> 9); | |
576 | bio_integrity_mark_head(bip, nr_sectors * bi->tuple_size); | |
577 | } | |
578 | EXPORT_SYMBOL(bio_integrity_advance); | |
579 | ||
580 | /** | |
581 | * bio_integrity_trim - Trim integrity vector | |
582 | * @bio: bio whose integrity vector to update | |
583 | * @offset: offset to first data sector | |
584 | * @sectors: number of data sectors | |
585 | * | |
586 | * Description: Used to trim the integrity vector in a cloned bio. | |
587 | * The ivec will be advanced corresponding to 'offset' data sectors | |
588 | * and the length will be truncated corresponding to 'len' data | |
589 | * sectors. | |
590 | */ | |
b984679e JA |
591 | void bio_integrity_trim(struct bio *bio, unsigned int offset, |
592 | unsigned int sectors) | |
7ba1ba12 MP |
593 | { |
594 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
595 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
596 | unsigned int nr_sectors; | |
597 | ||
598 | BUG_ON(bip == NULL); | |
599 | BUG_ON(bi == NULL); | |
600 | BUG_ON(!bio_flagged(bio, BIO_CLONED)); | |
601 | ||
602 | nr_sectors = bio_integrity_hw_sectors(bi, sectors); | |
603 | bip->bip_sector = bip->bip_sector + offset; | |
604 | bio_integrity_mark_head(bip, offset * bi->tuple_size); | |
605 | bio_integrity_mark_tail(bip, sectors * bi->tuple_size); | |
606 | } | |
607 | EXPORT_SYMBOL(bio_integrity_trim); | |
608 | ||
609 | /** | |
610 | * bio_integrity_split - Split integrity metadata | |
611 | * @bio: Protected bio | |
612 | * @bp: Resulting bio_pair | |
613 | * @sectors: Offset | |
614 | * | |
615 | * Description: Splits an integrity page into a bio_pair. | |
616 | */ | |
617 | void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors) | |
618 | { | |
619 | struct blk_integrity *bi; | |
620 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
621 | unsigned int nr_sectors; | |
622 | ||
623 | if (bio_integrity(bio) == 0) | |
624 | return; | |
625 | ||
626 | bi = bdev_get_integrity(bio->bi_bdev); | |
627 | BUG_ON(bi == NULL); | |
628 | BUG_ON(bip->bip_vcnt != 1); | |
629 | ||
630 | nr_sectors = bio_integrity_hw_sectors(bi, sectors); | |
631 | ||
632 | bp->bio1.bi_integrity = &bp->bip1; | |
633 | bp->bio2.bi_integrity = &bp->bip2; | |
634 | ||
635 | bp->iv1 = bip->bip_vec[0]; | |
636 | bp->iv2 = bip->bip_vec[0]; | |
637 | ||
638 | bp->bip1.bip_vec = &bp->iv1; | |
639 | bp->bip2.bip_vec = &bp->iv2; | |
640 | ||
641 | bp->iv1.bv_len = sectors * bi->tuple_size; | |
642 | bp->iv2.bv_offset += sectors * bi->tuple_size; | |
643 | bp->iv2.bv_len -= sectors * bi->tuple_size; | |
644 | ||
645 | bp->bip1.bip_sector = bio->bi_integrity->bip_sector; | |
646 | bp->bip2.bip_sector = bio->bi_integrity->bip_sector + nr_sectors; | |
647 | ||
648 | bp->bip1.bip_vcnt = bp->bip2.bip_vcnt = 1; | |
649 | bp->bip1.bip_idx = bp->bip2.bip_idx = 0; | |
650 | } | |
651 | EXPORT_SYMBOL(bio_integrity_split); | |
652 | ||
653 | /** | |
654 | * bio_integrity_clone - Callback for cloning bios with integrity metadata | |
655 | * @bio: New bio | |
656 | * @bio_src: Original bio | |
657 | * @bs: bio_set to allocate bip from | |
658 | * | |
659 | * Description: Called to allocate a bip when cloning a bio | |
660 | */ | |
b984679e JA |
661 | int bio_integrity_clone(struct bio *bio, struct bio *bio_src, |
662 | struct bio_set *bs) | |
7ba1ba12 MP |
663 | { |
664 | struct bio_integrity_payload *bip_src = bio_src->bi_integrity; | |
665 | struct bio_integrity_payload *bip; | |
666 | ||
667 | BUG_ON(bip_src == NULL); | |
668 | ||
669 | bip = bio_integrity_alloc_bioset(bio, GFP_NOIO, bip_src->bip_vcnt, bs); | |
670 | ||
671 | if (bip == NULL) | |
672 | return -EIO; | |
673 | ||
674 | memcpy(bip->bip_vec, bip_src->bip_vec, | |
675 | bip_src->bip_vcnt * sizeof(struct bio_vec)); | |
676 | ||
677 | bip->bip_sector = bip_src->bip_sector; | |
678 | bip->bip_vcnt = bip_src->bip_vcnt; | |
679 | bip->bip_idx = bip_src->bip_idx; | |
680 | ||
681 | return 0; | |
682 | } | |
683 | EXPORT_SYMBOL(bio_integrity_clone); | |
684 | ||
685 | int bioset_integrity_create(struct bio_set *bs, int pool_size) | |
686 | { | |
687 | bs->bio_integrity_pool = mempool_create_slab_pool(pool_size, | |
688 | bio_integrity_slab); | |
689 | if (!bs->bio_integrity_pool) | |
690 | return -1; | |
691 | ||
692 | return 0; | |
693 | } | |
694 | EXPORT_SYMBOL(bioset_integrity_create); | |
695 | ||
696 | void bioset_integrity_free(struct bio_set *bs) | |
697 | { | |
698 | if (bs->bio_integrity_pool) | |
699 | mempool_destroy(bs->bio_integrity_pool); | |
700 | } | |
701 | EXPORT_SYMBOL(bioset_integrity_free); | |
702 | ||
703 | void __init bio_integrity_init_slab(void) | |
704 | { | |
705 | bio_integrity_slab = KMEM_CACHE(bio_integrity_payload, | |
706 | SLAB_HWCACHE_ALIGN|SLAB_PANIC); | |
707 | } | |
7ba1ba12 MP |
708 | |
709 | static int __init integrity_init(void) | |
710 | { | |
711 | kintegrityd_wq = create_workqueue("kintegrityd"); | |
712 | ||
713 | if (!kintegrityd_wq) | |
714 | panic("Failed to create kintegrityd\n"); | |
715 | ||
716 | return 0; | |
717 | } | |
718 | subsys_initcall(integrity_init); |