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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 */ | |
74aa8c2c MP |
110 | if (!bio_flagged(bio, BIO_CLONED) && !bio_flagged(bio, BIO_FS_INTEGRITY) |
111 | && bip->bip_buf != NULL) | |
7ba1ba12 MP |
112 | kfree(bip->bip_buf); |
113 | ||
114 | mempool_free(bip->bip_vec, bs->bvec_pools[bip->bip_pool]); | |
115 | mempool_free(bip, bs->bio_integrity_pool); | |
116 | ||
117 | bio->bi_integrity = NULL; | |
118 | } | |
119 | EXPORT_SYMBOL(bio_integrity_free); | |
120 | ||
121 | /** | |
122 | * bio_integrity_add_page - Attach integrity metadata | |
123 | * @bio: bio to update | |
124 | * @page: page containing integrity metadata | |
125 | * @len: number of bytes of integrity metadata in page | |
126 | * @offset: start offset within page | |
127 | * | |
128 | * Description: Attach a page containing integrity metadata to bio. | |
129 | */ | |
130 | int bio_integrity_add_page(struct bio *bio, struct page *page, | |
131 | unsigned int len, unsigned int offset) | |
132 | { | |
133 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
134 | struct bio_vec *iv; | |
135 | ||
136 | if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_pool)) { | |
137 | printk(KERN_ERR "%s: bip_vec full\n", __func__); | |
138 | return 0; | |
139 | } | |
140 | ||
141 | iv = bip_vec_idx(bip, bip->bip_vcnt); | |
142 | BUG_ON(iv == NULL); | |
143 | BUG_ON(iv->bv_page != NULL); | |
144 | ||
145 | iv->bv_page = page; | |
146 | iv->bv_len = len; | |
147 | iv->bv_offset = offset; | |
148 | bip->bip_vcnt++; | |
149 | ||
150 | return len; | |
151 | } | |
152 | EXPORT_SYMBOL(bio_integrity_add_page); | |
153 | ||
9c02f2b0 JA |
154 | static int bdev_integrity_enabled(struct block_device *bdev, int rw) |
155 | { | |
156 | struct blk_integrity *bi = bdev_get_integrity(bdev); | |
157 | ||
158 | if (bi == NULL) | |
159 | return 0; | |
160 | ||
161 | if (rw == READ && bi->verify_fn != NULL && | |
162 | (bi->flags & INTEGRITY_FLAG_READ)) | |
163 | return 1; | |
164 | ||
165 | if (rw == WRITE && bi->generate_fn != NULL && | |
166 | (bi->flags & INTEGRITY_FLAG_WRITE)) | |
167 | return 1; | |
168 | ||
169 | return 0; | |
170 | } | |
171 | ||
7ba1ba12 MP |
172 | /** |
173 | * bio_integrity_enabled - Check whether integrity can be passed | |
174 | * @bio: bio to check | |
175 | * | |
176 | * Description: Determines whether bio_integrity_prep() can be called | |
177 | * on this bio or not. bio data direction and target device must be | |
178 | * set prior to calling. The functions honors the write_generate and | |
179 | * read_verify flags in sysfs. | |
180 | */ | |
181 | int bio_integrity_enabled(struct bio *bio) | |
182 | { | |
183 | /* Already protected? */ | |
184 | if (bio_integrity(bio)) | |
185 | return 0; | |
186 | ||
187 | return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio)); | |
188 | } | |
189 | EXPORT_SYMBOL(bio_integrity_enabled); | |
190 | ||
191 | /** | |
192 | * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto | |
193 | * @bi: blk_integrity profile for device | |
194 | * @sectors: Number of 512 sectors to convert | |
195 | * | |
196 | * Description: The block layer calculates everything in 512 byte | |
197 | * sectors but integrity metadata is done in terms of the hardware | |
198 | * sector size of the storage device. Convert the block layer sectors | |
199 | * to physical sectors. | |
200 | */ | |
b984679e JA |
201 | static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi, |
202 | unsigned int sectors) | |
7ba1ba12 MP |
203 | { |
204 | /* At this point there are only 512b or 4096b DIF/EPP devices */ | |
205 | if (bi->sector_size == 4096) | |
206 | return sectors >>= 3; | |
207 | ||
208 | return sectors; | |
209 | } | |
210 | ||
211 | /** | |
212 | * bio_integrity_tag_size - Retrieve integrity tag space | |
213 | * @bio: bio to inspect | |
214 | * | |
215 | * Description: Returns the maximum number of tag bytes that can be | |
216 | * attached to this bio. Filesystems can use this to determine how | |
217 | * much metadata to attach to an I/O. | |
218 | */ | |
219 | unsigned int bio_integrity_tag_size(struct bio *bio) | |
220 | { | |
221 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
222 | ||
223 | BUG_ON(bio->bi_size == 0); | |
224 | ||
225 | return bi->tag_size * (bio->bi_size / bi->sector_size); | |
226 | } | |
227 | EXPORT_SYMBOL(bio_integrity_tag_size); | |
228 | ||
229 | int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, int set) | |
230 | { | |
231 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
232 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
233 | unsigned int nr_sectors; | |
234 | ||
235 | BUG_ON(bip->bip_buf == NULL); | |
236 | ||
237 | if (bi->tag_size == 0) | |
238 | return -1; | |
239 | ||
b984679e JA |
240 | nr_sectors = bio_integrity_hw_sectors(bi, |
241 | DIV_ROUND_UP(len, bi->tag_size)); | |
7ba1ba12 MP |
242 | |
243 | if (nr_sectors * bi->tuple_size > bip->bip_size) { | |
244 | printk(KERN_ERR "%s: tag too big for bio: %u > %u\n", | |
245 | __func__, nr_sectors * bi->tuple_size, bip->bip_size); | |
246 | return -1; | |
247 | } | |
248 | ||
249 | if (set) | |
250 | bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors); | |
251 | else | |
252 | bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors); | |
253 | ||
254 | return 0; | |
255 | } | |
256 | ||
257 | /** | |
258 | * bio_integrity_set_tag - Attach a tag buffer to a bio | |
259 | * @bio: bio to attach buffer to | |
260 | * @tag_buf: Pointer to a buffer containing tag data | |
261 | * @len: Length of the included buffer | |
262 | * | |
263 | * Description: Use this function to tag a bio by leveraging the extra | |
264 | * space provided by devices formatted with integrity protection. The | |
265 | * size of the integrity buffer must be <= to the size reported by | |
266 | * bio_integrity_tag_size(). | |
267 | */ | |
268 | int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len) | |
269 | { | |
270 | BUG_ON(bio_data_dir(bio) != WRITE); | |
271 | ||
272 | return bio_integrity_tag(bio, tag_buf, len, 1); | |
273 | } | |
274 | EXPORT_SYMBOL(bio_integrity_set_tag); | |
275 | ||
276 | /** | |
277 | * bio_integrity_get_tag - Retrieve a tag buffer from a bio | |
278 | * @bio: bio to retrieve buffer from | |
279 | * @tag_buf: Pointer to a buffer for the tag data | |
280 | * @len: Length of the target buffer | |
281 | * | |
282 | * Description: Use this function to retrieve the tag buffer from a | |
283 | * completed I/O. The size of the integrity buffer must be <= to the | |
284 | * size reported by bio_integrity_tag_size(). | |
285 | */ | |
286 | int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len) | |
287 | { | |
288 | BUG_ON(bio_data_dir(bio) != READ); | |
289 | ||
290 | return bio_integrity_tag(bio, tag_buf, len, 0); | |
291 | } | |
292 | EXPORT_SYMBOL(bio_integrity_get_tag); | |
293 | ||
294 | /** | |
295 | * bio_integrity_generate - Generate integrity metadata for a bio | |
296 | * @bio: bio to generate integrity metadata for | |
297 | * | |
298 | * Description: Generates integrity metadata for a bio by calling the | |
299 | * block device's generation callback function. The bio must have a | |
300 | * bip attached with enough room to accommodate the generated | |
301 | * integrity metadata. | |
302 | */ | |
303 | static void bio_integrity_generate(struct bio *bio) | |
304 | { | |
305 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
306 | struct blk_integrity_exchg bix; | |
307 | struct bio_vec *bv; | |
308 | sector_t sector = bio->bi_sector; | |
309 | unsigned int i, sectors, total; | |
310 | void *prot_buf = bio->bi_integrity->bip_buf; | |
311 | ||
312 | total = 0; | |
313 | bix.disk_name = bio->bi_bdev->bd_disk->disk_name; | |
314 | bix.sector_size = bi->sector_size; | |
315 | ||
316 | bio_for_each_segment(bv, bio, i) { | |
317 | void *kaddr = kmap_atomic(bv->bv_page, KM_USER0); | |
318 | bix.data_buf = kaddr + bv->bv_offset; | |
319 | bix.data_size = bv->bv_len; | |
320 | bix.prot_buf = prot_buf; | |
321 | bix.sector = sector; | |
322 | ||
323 | bi->generate_fn(&bix); | |
324 | ||
325 | sectors = bv->bv_len / bi->sector_size; | |
326 | sector += sectors; | |
327 | prot_buf += sectors * bi->tuple_size; | |
328 | total += sectors * bi->tuple_size; | |
329 | BUG_ON(total > bio->bi_integrity->bip_size); | |
330 | ||
331 | kunmap_atomic(kaddr, KM_USER0); | |
332 | } | |
333 | } | |
334 | ||
9c02f2b0 JA |
335 | static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi) |
336 | { | |
337 | if (bi) | |
338 | return bi->tuple_size; | |
339 | ||
340 | return 0; | |
341 | } | |
342 | ||
7ba1ba12 MP |
343 | /** |
344 | * bio_integrity_prep - Prepare bio for integrity I/O | |
345 | * @bio: bio to prepare | |
346 | * | |
347 | * Description: Allocates a buffer for integrity metadata, maps the | |
348 | * pages and attaches them to a bio. The bio must have data | |
349 | * direction, target device and start sector set priot to calling. In | |
350 | * the WRITE case, integrity metadata will be generated using the | |
351 | * block device's integrity function. In the READ case, the buffer | |
352 | * will be prepared for DMA and a suitable end_io handler set up. | |
353 | */ | |
354 | int bio_integrity_prep(struct bio *bio) | |
355 | { | |
356 | struct bio_integrity_payload *bip; | |
357 | struct blk_integrity *bi; | |
358 | struct request_queue *q; | |
359 | void *buf; | |
360 | unsigned long start, end; | |
361 | unsigned int len, nr_pages; | |
362 | unsigned int bytes, offset, i; | |
363 | unsigned int sectors; | |
364 | ||
365 | bi = bdev_get_integrity(bio->bi_bdev); | |
366 | q = bdev_get_queue(bio->bi_bdev); | |
367 | BUG_ON(bi == NULL); | |
368 | BUG_ON(bio_integrity(bio)); | |
369 | ||
370 | sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio)); | |
371 | ||
372 | /* Allocate kernel buffer for protection data */ | |
373 | len = sectors * blk_integrity_tuple_size(bi); | |
374 | buf = kmalloc(len, GFP_NOIO | __GFP_NOFAIL | q->bounce_gfp); | |
375 | if (unlikely(buf == NULL)) { | |
376 | printk(KERN_ERR "could not allocate integrity buffer\n"); | |
377 | return -EIO; | |
378 | } | |
379 | ||
380 | end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
381 | start = ((unsigned long) buf) >> PAGE_SHIFT; | |
382 | nr_pages = end - start; | |
383 | ||
384 | /* Allocate bio integrity payload and integrity vectors */ | |
385 | bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages); | |
386 | if (unlikely(bip == NULL)) { | |
387 | printk(KERN_ERR "could not allocate data integrity bioset\n"); | |
388 | kfree(buf); | |
389 | return -EIO; | |
390 | } | |
391 | ||
392 | bip->bip_buf = buf; | |
393 | bip->bip_size = len; | |
394 | bip->bip_sector = bio->bi_sector; | |
395 | ||
396 | /* Map it */ | |
397 | offset = offset_in_page(buf); | |
398 | for (i = 0 ; i < nr_pages ; i++) { | |
399 | int ret; | |
400 | bytes = PAGE_SIZE - offset; | |
401 | ||
402 | if (len <= 0) | |
403 | break; | |
404 | ||
405 | if (bytes > len) | |
406 | bytes = len; | |
407 | ||
408 | ret = bio_integrity_add_page(bio, virt_to_page(buf), | |
409 | bytes, offset); | |
410 | ||
411 | if (ret == 0) | |
412 | return 0; | |
413 | ||
414 | if (ret < bytes) | |
415 | break; | |
416 | ||
417 | buf += bytes; | |
418 | len -= bytes; | |
419 | offset = 0; | |
420 | } | |
421 | ||
422 | /* Install custom I/O completion handler if read verify is enabled */ | |
423 | if (bio_data_dir(bio) == READ) { | |
424 | bip->bip_end_io = bio->bi_end_io; | |
425 | bio->bi_end_io = bio_integrity_endio; | |
426 | } | |
427 | ||
428 | /* Auto-generate integrity metadata if this is a write */ | |
429 | if (bio_data_dir(bio) == WRITE) | |
430 | bio_integrity_generate(bio); | |
431 | ||
432 | return 0; | |
433 | } | |
434 | EXPORT_SYMBOL(bio_integrity_prep); | |
435 | ||
436 | /** | |
437 | * bio_integrity_verify - Verify integrity metadata for a bio | |
438 | * @bio: bio to verify | |
439 | * | |
440 | * Description: This function is called to verify the integrity of a | |
441 | * bio. The data in the bio io_vec is compared to the integrity | |
442 | * metadata returned by the HBA. | |
443 | */ | |
444 | static int bio_integrity_verify(struct bio *bio) | |
445 | { | |
446 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
447 | struct blk_integrity_exchg bix; | |
448 | struct bio_vec *bv; | |
449 | sector_t sector = bio->bi_integrity->bip_sector; | |
450 | unsigned int i, sectors, total, ret; | |
451 | void *prot_buf = bio->bi_integrity->bip_buf; | |
452 | ||
453 | ret = total = 0; | |
454 | bix.disk_name = bio->bi_bdev->bd_disk->disk_name; | |
455 | bix.sector_size = bi->sector_size; | |
456 | ||
457 | bio_for_each_segment(bv, bio, i) { | |
458 | void *kaddr = kmap_atomic(bv->bv_page, KM_USER0); | |
459 | bix.data_buf = kaddr + bv->bv_offset; | |
460 | bix.data_size = bv->bv_len; | |
461 | bix.prot_buf = prot_buf; | |
462 | bix.sector = sector; | |
463 | ||
464 | ret = bi->verify_fn(&bix); | |
465 | ||
466 | if (ret) { | |
467 | kunmap_atomic(kaddr, KM_USER0); | |
468 | break; | |
469 | } | |
470 | ||
471 | sectors = bv->bv_len / bi->sector_size; | |
472 | sector += sectors; | |
473 | prot_buf += sectors * bi->tuple_size; | |
474 | total += sectors * bi->tuple_size; | |
475 | BUG_ON(total > bio->bi_integrity->bip_size); | |
476 | ||
477 | kunmap_atomic(kaddr, KM_USER0); | |
478 | } | |
479 | ||
480 | return ret; | |
481 | } | |
482 | ||
483 | /** | |
484 | * bio_integrity_verify_fn - Integrity I/O completion worker | |
485 | * @work: Work struct stored in bio to be verified | |
486 | * | |
487 | * Description: This workqueue function is called to complete a READ | |
488 | * request. The function verifies the transferred integrity metadata | |
489 | * and then calls the original bio end_io function. | |
490 | */ | |
491 | static void bio_integrity_verify_fn(struct work_struct *work) | |
492 | { | |
b984679e | 493 | struct bio_integrity_payload *bip = |
7ba1ba12 MP |
494 | container_of(work, struct bio_integrity_payload, bip_work); |
495 | struct bio *bio = bip->bip_bio; | |
496 | int error = bip->bip_error; | |
497 | ||
498 | if (bio_integrity_verify(bio)) { | |
499 | clear_bit(BIO_UPTODATE, &bio->bi_flags); | |
500 | error = -EIO; | |
501 | } | |
502 | ||
503 | /* Restore original bio completion handler */ | |
504 | bio->bi_end_io = bip->bip_end_io; | |
505 | ||
506 | if (bio->bi_end_io) | |
507 | bio->bi_end_io(bio, error); | |
508 | } | |
509 | ||
510 | /** | |
511 | * bio_integrity_endio - Integrity I/O completion function | |
512 | * @bio: Protected bio | |
513 | * @error: Pointer to errno | |
514 | * | |
515 | * Description: Completion for integrity I/O | |
516 | * | |
517 | * Normally I/O completion is done in interrupt context. However, | |
518 | * verifying I/O integrity is a time-consuming task which must be run | |
519 | * in process context. This function postpones completion | |
520 | * accordingly. | |
521 | */ | |
522 | void bio_integrity_endio(struct bio *bio, int error) | |
523 | { | |
524 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
525 | ||
526 | BUG_ON(bip->bip_bio != bio); | |
527 | ||
528 | bip->bip_error = error; | |
529 | INIT_WORK(&bip->bip_work, bio_integrity_verify_fn); | |
530 | queue_work(kintegrityd_wq, &bip->bip_work); | |
531 | } | |
532 | EXPORT_SYMBOL(bio_integrity_endio); | |
533 | ||
534 | /** | |
535 | * bio_integrity_mark_head - Advance bip_vec skip bytes | |
536 | * @bip: Integrity vector to advance | |
537 | * @skip: Number of bytes to advance it | |
538 | */ | |
b984679e JA |
539 | void bio_integrity_mark_head(struct bio_integrity_payload *bip, |
540 | unsigned int skip) | |
7ba1ba12 MP |
541 | { |
542 | struct bio_vec *iv; | |
543 | unsigned int i; | |
544 | ||
545 | bip_for_each_vec(iv, bip, i) { | |
546 | if (skip == 0) { | |
547 | bip->bip_idx = i; | |
548 | return; | |
549 | } else if (skip >= iv->bv_len) { | |
550 | skip -= iv->bv_len; | |
551 | } else { /* skip < iv->bv_len) */ | |
552 | iv->bv_offset += skip; | |
553 | iv->bv_len -= skip; | |
554 | bip->bip_idx = i; | |
555 | return; | |
556 | } | |
557 | } | |
558 | } | |
559 | ||
560 | /** | |
561 | * bio_integrity_mark_tail - Truncate bip_vec to be len bytes long | |
562 | * @bip: Integrity vector to truncate | |
563 | * @len: New length of integrity vector | |
564 | */ | |
b984679e JA |
565 | void bio_integrity_mark_tail(struct bio_integrity_payload *bip, |
566 | unsigned int len) | |
7ba1ba12 MP |
567 | { |
568 | struct bio_vec *iv; | |
569 | unsigned int i; | |
570 | ||
571 | bip_for_each_vec(iv, bip, i) { | |
572 | if (len == 0) { | |
573 | bip->bip_vcnt = i; | |
574 | return; | |
575 | } else if (len >= iv->bv_len) { | |
576 | len -= iv->bv_len; | |
577 | } else { /* len < iv->bv_len) */ | |
578 | iv->bv_len = len; | |
579 | len = 0; | |
580 | } | |
581 | } | |
582 | } | |
583 | ||
584 | /** | |
585 | * bio_integrity_advance - Advance integrity vector | |
586 | * @bio: bio whose integrity vector to update | |
587 | * @bytes_done: number of data bytes that have been completed | |
588 | * | |
589 | * Description: This function calculates how many integrity bytes the | |
590 | * number of completed data bytes correspond to and advances the | |
591 | * integrity vector accordingly. | |
592 | */ | |
593 | void bio_integrity_advance(struct bio *bio, unsigned int bytes_done) | |
594 | { | |
595 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
596 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
597 | unsigned int nr_sectors; | |
598 | ||
599 | BUG_ON(bip == NULL); | |
600 | BUG_ON(bi == NULL); | |
601 | ||
602 | nr_sectors = bio_integrity_hw_sectors(bi, bytes_done >> 9); | |
603 | bio_integrity_mark_head(bip, nr_sectors * bi->tuple_size); | |
604 | } | |
605 | EXPORT_SYMBOL(bio_integrity_advance); | |
606 | ||
607 | /** | |
608 | * bio_integrity_trim - Trim integrity vector | |
609 | * @bio: bio whose integrity vector to update | |
610 | * @offset: offset to first data sector | |
611 | * @sectors: number of data sectors | |
612 | * | |
613 | * Description: Used to trim the integrity vector in a cloned bio. | |
614 | * The ivec will be advanced corresponding to 'offset' data sectors | |
615 | * and the length will be truncated corresponding to 'len' data | |
616 | * sectors. | |
617 | */ | |
b984679e JA |
618 | void bio_integrity_trim(struct bio *bio, unsigned int offset, |
619 | unsigned int sectors) | |
7ba1ba12 MP |
620 | { |
621 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
622 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
623 | unsigned int nr_sectors; | |
624 | ||
625 | BUG_ON(bip == NULL); | |
626 | BUG_ON(bi == NULL); | |
627 | BUG_ON(!bio_flagged(bio, BIO_CLONED)); | |
628 | ||
629 | nr_sectors = bio_integrity_hw_sectors(bi, sectors); | |
630 | bip->bip_sector = bip->bip_sector + offset; | |
631 | bio_integrity_mark_head(bip, offset * bi->tuple_size); | |
632 | bio_integrity_mark_tail(bip, sectors * bi->tuple_size); | |
633 | } | |
634 | EXPORT_SYMBOL(bio_integrity_trim); | |
635 | ||
636 | /** | |
637 | * bio_integrity_split - Split integrity metadata | |
638 | * @bio: Protected bio | |
639 | * @bp: Resulting bio_pair | |
640 | * @sectors: Offset | |
641 | * | |
642 | * Description: Splits an integrity page into a bio_pair. | |
643 | */ | |
644 | void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors) | |
645 | { | |
646 | struct blk_integrity *bi; | |
647 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
648 | unsigned int nr_sectors; | |
649 | ||
650 | if (bio_integrity(bio) == 0) | |
651 | return; | |
652 | ||
653 | bi = bdev_get_integrity(bio->bi_bdev); | |
654 | BUG_ON(bi == NULL); | |
655 | BUG_ON(bip->bip_vcnt != 1); | |
656 | ||
657 | nr_sectors = bio_integrity_hw_sectors(bi, sectors); | |
658 | ||
659 | bp->bio1.bi_integrity = &bp->bip1; | |
660 | bp->bio2.bi_integrity = &bp->bip2; | |
661 | ||
662 | bp->iv1 = bip->bip_vec[0]; | |
663 | bp->iv2 = bip->bip_vec[0]; | |
664 | ||
665 | bp->bip1.bip_vec = &bp->iv1; | |
666 | bp->bip2.bip_vec = &bp->iv2; | |
667 | ||
668 | bp->iv1.bv_len = sectors * bi->tuple_size; | |
669 | bp->iv2.bv_offset += sectors * bi->tuple_size; | |
670 | bp->iv2.bv_len -= sectors * bi->tuple_size; | |
671 | ||
672 | bp->bip1.bip_sector = bio->bi_integrity->bip_sector; | |
673 | bp->bip2.bip_sector = bio->bi_integrity->bip_sector + nr_sectors; | |
674 | ||
675 | bp->bip1.bip_vcnt = bp->bip2.bip_vcnt = 1; | |
676 | bp->bip1.bip_idx = bp->bip2.bip_idx = 0; | |
677 | } | |
678 | EXPORT_SYMBOL(bio_integrity_split); | |
679 | ||
680 | /** | |
681 | * bio_integrity_clone - Callback for cloning bios with integrity metadata | |
682 | * @bio: New bio | |
683 | * @bio_src: Original bio | |
684 | * @bs: bio_set to allocate bip from | |
685 | * | |
686 | * Description: Called to allocate a bip when cloning a bio | |
687 | */ | |
b984679e JA |
688 | int bio_integrity_clone(struct bio *bio, struct bio *bio_src, |
689 | struct bio_set *bs) | |
7ba1ba12 MP |
690 | { |
691 | struct bio_integrity_payload *bip_src = bio_src->bi_integrity; | |
692 | struct bio_integrity_payload *bip; | |
693 | ||
694 | BUG_ON(bip_src == NULL); | |
695 | ||
696 | bip = bio_integrity_alloc_bioset(bio, GFP_NOIO, bip_src->bip_vcnt, bs); | |
697 | ||
698 | if (bip == NULL) | |
699 | return -EIO; | |
700 | ||
701 | memcpy(bip->bip_vec, bip_src->bip_vec, | |
702 | bip_src->bip_vcnt * sizeof(struct bio_vec)); | |
703 | ||
704 | bip->bip_sector = bip_src->bip_sector; | |
705 | bip->bip_vcnt = bip_src->bip_vcnt; | |
706 | bip->bip_idx = bip_src->bip_idx; | |
707 | ||
708 | return 0; | |
709 | } | |
710 | EXPORT_SYMBOL(bio_integrity_clone); | |
711 | ||
712 | int bioset_integrity_create(struct bio_set *bs, int pool_size) | |
713 | { | |
714 | bs->bio_integrity_pool = mempool_create_slab_pool(pool_size, | |
715 | bio_integrity_slab); | |
716 | if (!bs->bio_integrity_pool) | |
717 | return -1; | |
718 | ||
719 | return 0; | |
720 | } | |
721 | EXPORT_SYMBOL(bioset_integrity_create); | |
722 | ||
723 | void bioset_integrity_free(struct bio_set *bs) | |
724 | { | |
725 | if (bs->bio_integrity_pool) | |
726 | mempool_destroy(bs->bio_integrity_pool); | |
727 | } | |
728 | EXPORT_SYMBOL(bioset_integrity_free); | |
729 | ||
730 | void __init bio_integrity_init_slab(void) | |
731 | { | |
732 | bio_integrity_slab = KMEM_CACHE(bio_integrity_payload, | |
733 | SLAB_HWCACHE_ALIGN|SLAB_PANIC); | |
734 | } | |
7ba1ba12 MP |
735 | |
736 | static int __init integrity_init(void) | |
737 | { | |
738 | kintegrityd_wq = create_workqueue("kintegrityd"); | |
739 | ||
740 | if (!kintegrityd_wq) | |
741 | panic("Failed to create kintegrityd\n"); | |
742 | ||
743 | return 0; | |
744 | } | |
745 | subsys_initcall(integrity_init); |