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